INTERNATIONAL CONFERENСE
“ORGANIC NANOPHOTONICS”
(ICON-RUSSIA 2009)
SYMPOSIUM
“MOLECULAR PHOTONICS”
Dedicated to Academician A.N.Terenin
SYMPOSIUM
“FUNDAMENTAL PRINCIPLES OF NANOPHOTONICS”
BOOK OF ABSTRACTS
June 21-28, 2009
St. Petersburg, Russia
Ministry of Education and Science of the Russian Federation
Russian Foundation for Basic Research
Russian Academy of Sciences
Saint-Petersburg State University
St.Petersburg State University of Information Technologies,
Mechanics and Optics
Photochemistry Center RAS
Institute of Problems of Chemical Physics RAS
Consortium “Organic Nanophotonics”
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CONTENTS
INTERNATIONAL CONFERENCE “ORGANIC NANOPHOTONICS” .....................15
ORALS ................................................................................................................15
LINEAR AND NONLINEAR OPTICAL PROPERTIES OF UV-INDUCED GOLD NANOPARTICLES
IN POLYMERIC MATRICES
Afanasiev A.V., Alexandrov A.P., Mochalova A.E., Smirnova L.A., Bityurin N.M. ................................... 15
FEMTOSECOND NANOPHOTONICS OF GOLD AND SILVER CLUSTERS PHOTODEPOSITED
ON CRYSTALLINE AND AMORPHOUS MESOPOROUS FILMS OF TiO2
Aiboushev A., Astafiev A., Nadtochenko V., Sarkisov O.M. ....................................................................... 16
DISSOCIATIVE LUMINESCENT SENSOR BASED ON QUANTUM DOT/ORGANIC MOLECULE
SYSTEM
Baranov A.V., Maslov V.G., Orlova A.O., Toporova Yu.A., Ushakova E.V., Fedorov A.V., Cherevkov S.A. 17
SELF-AGGREGATION OF LUMINESCENT SILICA NANOPARTICLES IN AQUEOUS
SOLUTIONS OF AMPHIPHILIC COMPOUNDS AND SURFACTANTS
Fedorenko S.V., Mustafina A.R., Konovalova O.D., Konovalov A.I. ........................................................ 18
INCOHERENT ENERGY TRANSFER IN QUANTUM DOTS: TIME-DOMAIN LUMINESCENT
SPECTROSCOPY
Fedorov A.V., Baranov A.V., Kruchinin S.Yu., Ushakova E.V., Savelyeva A.V., Mukhina M.V ............... 19
THEORY OF OPTICAL NANO MANIPULATION
Ishihara H., Iida T., Ajiki H. ...................................................................................................................... 20
SILICON NANOPHOTONICS: PRESENT STATUS AND PERSPECTIVES
Khriachtchev L. .......................................................................................................................................... 21
NOVEL NANOCOMPOSITE MATERIALS BASED ON MESOMORPHIC GLASSES OF METAL
ALKANOATES: STRUCTURES AND NONLINEAR-OPTICAL PROPERTIES
Klimusheva G., Garbovskiy Y., Bugaychuk S., Tolochko A., Mirnaya T. .................................................. 22
ELECTROLUMINESCENCE OF ORGANIC MOLECULES IN BLUE-GREEN AND RED RANGES
OF THE SPECTRUM
Kopylova T.N., Mayer G.V., Gadirov R.M., Degtyarenko K.M., Egorova A.V., Eremina N.S., Kukhto A.V.,
Meshkova S.B., Topilova Z.M., Shul’gin V.F., Samsonova L.G. ............................................................... 23
LEPR STUDY OF CHARGE TRANSFER PHOTOINDUCED IN POLYMER/FULLERENE BULK
HETEROJUNCTIONS
Krinichnyi V.I., Yudanova E.I., Denisov N.N. ........................................................................................... 24
OPTICAL AND ELECTROPHYSICAL PROPERTIES AND APPLICATIONS OF ORGANIC AND
ORGANIC-INORGANIC THIN FILM NANOSTRUCTURES
Kukhta A.V. ................................................................................................................................................ 25
EFFECT OF J-AGGREGATES ON OPTOELECTRONIC PROPERTIES OF CONDUCTING
POLYMERS
Maltsev E.I., Lypenko D.A., Perelygina O.M., Pozin S.I., Vannikov A.V. ................................................. 26
FABRICATION OF NANO SPACE FOR CONTROL OF INCIDENT LIGHT FIELD
Masuda H., Kondo T. ................................................................................................................................. 27
LASER AND ORGANIC NANOPARTICLES
Masuhara H. .............................................................................................................................................. 28
QUANTITATIVE ANALYSIS OF PH AND METAL IONS SENSITIVE PHOTOCHROMIC
SPIROPYRANS AND SPIROOXAZINES
Micheau J.C. .............................................................................................................................................. 29
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CALIXARENE-BASED COMPLEXES AS PROMISING LUMINOPHORES FOR LUMINESCENT
SILICA NANOPARTICLES
Mustafina A.R., Fedorenko S.V., Konovalova O.D., Konovalov A.I. ........................................................ 30
LOW-THRESHOLD TRANSFORMATION OF FREQUENCY IN SOLID SOLUTIONS OF Zn0.6Cd0.4S
WITH ADSORBED METAL-ORGANIC CLUSTERS
Ovchinnikov O.V., Smirnov M.S., Leonova L.Yu., Kosjakova E.A., Latyshev A.N., Kluyev V.G. .............. 31
SUPRAMOLECULAR WATER-SOLUBLE COMPLEXES OF CAROTENOIDS
Polyakov N.E., Leshina T.V., Meteleva E.S., Dushkin A.V., Konovalova T.A., Kispert L.D. .................... 32
BRANCHED AND DENDRITIC POLYARYLSILANES AS NANOSTRUCTURED
LUMINOPHORES
Ponomаrenko S.A., Surin N.M., Borshchev O.V., Luponosov Y.N., Shumilkina E.A., Muzafarov A.M. ... 33
THE EFFECT OF METALIC NANOPARTICLES ON THE OPTICAL CHARACTERISICS OF
PORPHYNATES AND MEH-PPV SOLUTIONS
Revina A.A., Tedoradze M.G., Plachev Yu.A., Bogdanova I.V. ................................................................. 34
SPECTRAL AND LUMINESCENT PROPERTIES OF SEVEREL ACRIDINE COMPOUNDS IN
SOLUTIONS AND SiO2-FILMS
Samsonova L.G., Selivanov N.I., Kopylova T.N., Artyukhov V.Ya., Solodova T.A. ................................... 35
OPTOELECTRONIC SENSOR SYSTEMS BASED ON THIN FILM ORGANIC ELECTRONICS
Schoo H.F.M., Koetse M.M., Rensing P.A., Van Heck G.T., Meulendijks N.N.M.M., De Kok M., Kruijt
P.G.M., Wieringa F.P. ............................................................................................................................... 36
FULLERENE NANOCLUSTERS AS AMPLIFIERS IN LINEAR SPECTROSCOPY AND NONLINEAR OPTICS
Sheka E.F. .................................................................................................................................................. 37
FEMTOSECOND PRIMARY CHARGE SEPARATION IN PHOTOSYSTEM I
Shelaev I.V., Gostev F.E., Mamedov M., Sarkisov O.M., Nadtochenko V.A., Suvalov V.A., Semenov A.Yu. 38
ELECTRONIC SENSORS ON THE BASIS OF NANOSTRUCTURED CERIUM OXIDE FILMS
Shmyryeva A.N., Borisov A.V., Maksimchuk N.V. ..................................................................................... 39
UV-LIGHT STIMULATED FORMATION OF ORGANIC NANOPARTICLES
Skubnevskaya G.I., Dubtsov S.N., Dultseva G.G. ...................................................................................... 40
MATERIAL SOLUBILITY AND MISCIBILITY EFFECTS IN FULLERENE/POLYMER
COMPOSITES USED AS PHOTOACTIVE MATERIALS IN ORGANIC SOLAR CELLS
Troshin P.A., Khakina E.A., Susarova D.K., Hoppe H., Goryachev A.E., Peregudov A.S., Sariciftci N.S.,
Razumov V.F. ............................................................................................................................................. 41
PEPTIDES AGGREGATES AS SUPRAMOLECULAR NANOSYSTEMS. STRUCTURE
INVESTIGATIONS BY PULSED ELECTRON-ELECTRON DOUBLE RESONANCE (PELDOR)
SPECTROSCOPY
Tsvetkov Yu.D., Milov A.D., Samoilova R.I. .............................................................................................. 42
NON-LINEAR OPTICAL AND PHOTONIC CRYSTALLINE CHROMOPHORE-CONTAINING
POLYMERIC MATERIALS FOR OPTOELECTRONICS AND OPTOSENSORICS
Yakimansky A.V., Nosova G.I., Solovskaya N.A., Smirnov N.N., Nikonorova N.A., Menshikova A.Yu.,
Shevchenko N.N., Evseeva T.G., Gromov S.P., Sazonov S.K., Koshkin A.V., Sazhnikov V.A., Alfimov M.V.
..................................................................................................................................................................... 43
FORMATION PRINCIPLES AND RELAXATION PROCESSES IN NANOSCALE
HETEROGENEOUS COMPLEXES: MULTIPORPHYRIN ARRAYS AND CdSe/ZnS
NANOCRYSTALS
Zenkevich E.I., Von Borczyskowski C. ....................................................................................................... 44
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POSTERS............................................................................................................45
PHOTONICS OF THE NON-CONJUGATED POLYARYLENEPHTHALIDES – NEW POLYMER
CLASS FOR ELECTROLUMINESCENCE DEVICES
Antipin V.A., Lachinov A.N., Nakaryakov A.S., Salazkin S.N., Kovalev A.A., Kazakov V.P ............... 45
MODELING OF NONLINEAR-OPTICAL ACTIVITY OF POLYMER ELECTRET AND
RELAXATION STABILITY OF ITS QUADRATIC RESPONSE
Balakina M.Yu ........................................................................................................................................... 46
CONTINUUM MODEL FOR ELECTROSTATIC ENERGY OF INTERACTION OF A DIPOLAR ION
OR DIPOLAR MOLECULAR SYSTEM IMMERSED IN A SPHERICAL NANOPARTICLE
Basilevsky M.V., Nikitina E.A., Grigoriev F.V., Alfimov M.V ............................................................... 47
OPTICAL CONTROL OF NANOPOROUS POLYMERS SYNTHESIS PROCESS FROM
PHOTOPOLYMERIZABLE COMPOSITES
Batenkin M.A., Konev A.N., Mensov S.N., Chesnokov S.A .................................................................... 48
SYNTHESIS, SELECTIVE AND PHOTOLUMINESCENT PROPERTIES OF THE DERIVATIVES
OF TERPYRIDINES - EFFECTIVE MOLECULAR RECEPTORS FOR ZINC(II) ION
Baulin V.E., Logacheva N.M., Safiulina A.M., Konstantinov N.Y., Tsivadze A.Y ................................. 49
PHOTOLUMINESCENT PROPERTIES OF FLUORENE-SUBSTITUTED PORPHYRINS
Chernyadyev A.Yu., Plachev Yu.A., Tsivadze A.Yu ................................................................................ 50
PHOTOCHROMISM OF MEROCYANINE COMPLEXES OF DIPHENYLOXAZOL CONTAINING
SPIROPYRANS WITH TRANSITION METAL CATIONS
Chernyshev A.V., Metelitsa A.V., Gaeva E.B., Voloshin N.A., Minkin V.I ............................................ 51
MECHANOCHEMICAL PREPARATION OF WATER-SOLUBLE COMPLEXES OF
CAROTENOIDS
Evseenko V.I., Meteleva E.S., Dushkin A.V., Polyakov N.E ................................................................... 52
EFFECT OF THE CHROMOPHORES MUTUAL ORIENTATION ON NONLINEAR-OPTICAL
RESPONSE OF MOLECULAR SYSTEM. QUANTUM-CHEMICAL CALCULATIONS
Fominykh O.D., Balakina M.Yu ................................................................................................................ 53
INFLUENCE OF THE ORGANIC LIGHT-EMITTING DIODE STRUCTURE ON THE IR(PPY)3
ELECTROLUMINESCENCE
Gadirov R.M., Degtyarenko K.M., Eremina N.S., Kopylova T.N ............................................................ 54
MODEL OF ENERGY CONVERSION EFFICIENCY FOR POLYMER PHOTOVOLTAIC CELLS
Godovsky D.Yu., Inganas O ...................................................................................................................... 55
PHOTOPHYSICAL PROPERTIES OF AQUEOUS SOLUTION OF 3,3’DIETHYLTHIACARBOCYANINE IODIDE IN THE PRESENCE OF CUCURBIT[7]URIL
Golubkov D.V., Ivanov D.A., Petrov N.Kh., Alfimov M.V ...................................................................... 56
TRIPLET-TRIPLET ENERGY TRANSFER IN NANODIMENSIONAL MOLECULAR LAYERS
Ibrayev N.Kh., Aimukhanov A.K., Seliverstova E.V ................................................................................ 57
SPECTROSCOPIC PROPERTIES OF LANGMUIR FILMS OF RHODAMINE DYES AND
POLYAMPHOLYTIC POLYMER
Ibrayev N.Kh., Smagulov Zh.K., Аlekseeva V.I., Marinina L.E., Savvina L.P ........................................ 58
NEW BLUE- AND GREEN-LIGHT-EMITTING ELECTROLUMINESCENT POLYFLUORENES
WITH 7,8,10-TRIARYLFLUORINE AERIAL FRAGMENTS IN BACKBONE
Keshtov M.L., Lypenko D.A., Pozin S.I., Maltsev E.I., Maltsev E.I ........................................................ 59
[C60(CN)5]-: A REMARKABLY STABLE [60]FULLERENE ANION
Khakina E.A., Troshin P.A., Konarev D.V., Peregudov A.S., Soulimenkov I.V., Peregudova S.M.,
Lyubovskaya R.N ...................................................................................................................................... 60
SPECTRAL AND SENSING PROPERTIES OF 9-DTAA DYE IN POLYMER MATRICES
Khlebunov A.A., Komarov P.V., Ionov D.S., Koshkin A.V., Sazhnikov V.A., Alfimov M.V ................ 61
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POLYSUBSTITUTED DERIVATIVES OF PALLADIUM TETRAPHENYL
TETRABENZOPORPHYRIN. SYNTHESIS AND PROPERTIES
Khoroshutin A.V., Chumakov D.E., Uzhinov B.M., Anisimov A.V ........................................................ 62
STRUCTURE AND NONLINEAR OPTICAL PROPERTIES OF BILAYER CELLS WITH ORGANIC
AND SEMICONDUCTOR NANOFILMS COVERED BY LYOTROPIC MESOPHASE OF METAL
ALKANOATES
Klimusheva G., Garbovskiy Yu., Bugaychuk S., Tolochko A., Mirnaya T .............................................. 63
INVESTIGATION OF DEGRADATION PROCESSES IN ORGANIC LIGHT-EMITTING DEVICES
Kondracki B.A., Usov N.N., Kruchinin A.U ............................................................................................. 64
DERIVATIVES OF DIVINYLBENZOXAZOLYLBIPHENYL: NEW ELECTROLUMINESCENT
MATERIALS
Kopylova T.N., Kukhto A.V., Kolesnik I.N., Kukhto I.N., Galinovski N.A., Degtyarenko K.M., Eremina
N.S., Gadirov R.M ..................................................................................................................................... 65
MAGNETIC FIELD EFFECT ON THE POLYARYLENEPHTHALIDES ELECTROLUMINESCENCE
Kovalev A.A., Antipin V.A., Lachinov A.N., Salazkin S.N., Kazakov V.P ............................................. 66
EXIPLEX ELECTROLUMINESCENCE SPECTRA IN THE ORGANIC LIGHT-EMITTING DIODES
BASED ON SULPHANYLAMINO ZINC COMPLEXES
Krasnikova S.S., Kaplunov M.G., Yakushchenko I.K .............................................................................. 67
INFLUENCE OF ETHANOL VAPORS ON SPECTRAL BEHAVIOR OF NILE RED IN ORGANICSILICATE MATRIX
Lupikov D.I., Movchan T.G ...................................................................................................................... 68
EFFICIENT MULTILAYER ELECTROLUMINESCENT ORGANIC STRUCTURES BASED ON
IRIDIUM(III) COMPLEX
Lypenko D.A., Dmitriev A.V., Maltsev E.I., Vannikov A.V .................................................................... 69
DYNAMICS OF ABSORPTION AND LUMINESCENCE OF CdSe/ZnS QUANTUM DOTS IN THE
PROCESS OF AGGREGATION IN HYDROPHOBIC SOLUTIONS
Maslov V.G., Adrianov V.E., Orlova A.O., Baranov A.V., Fedorov A.V ................................................ 70
QUENCHING OF ELECTRONICALLY EXCITED CARBAZOLE BY A STABLE IMIDAZOLIDINE
RADICAL
Matveeva A.G., Stass D.V., Korolev V.V., Plyusnin V.F., Reznikov V.A ............................................... 71
OPTICAL FORMATION OF GRADED-INDEX WAVEGUIDE STRUCTURES IN
PHOTOPOLYMERIZABLE COMPOSITES
Mensov S.N., Polushtaytsev Yu.V ............................................................................................................. 72
NOVEL PHOTOCHROMIC SPIROPYRAN CATIONS WITH A PYRIDINIUM MOIETY IN THE
ALIPHATIC SIDE CHAIN
Metelitsa A.V., Besugliy S.O., Voloshin N.A., Soloveva E.V., Minkin V.I ............................................. 73
THEORETICAL STUDY OF ADSORPTION OF AN ACRIDINE DYE AND SIMPLE MOLECULES
ON A SILICA SURFACE
Minibaev R.F., Zhuravlev N.A., Bagaturyants A.A., Alfimov M.V ......................................................... 74
SPECTRAL BEHAVIOUR OF NILE RED IN ORGANIC-SILICATE SOL-GEL MATRIСES
Movchan T.G., Lupicov D.I., Khamova T.V., Shilova O.A ...................................................................... 75
NEW PHOTOCHROMIC ASYMMETRIC BISPIROPYRAN OF THE 2,3-DIHYDRO-4-OXONAPHTO[2,1-E]OXAZINE SERIE
Mukhanov E.L., Lukyanov B.S., Dorogan I.V., Besuglui S.O., Alexeenko Yu.S., Ryashin O.N., Tkachev
V.V ............................................................................................................................................................. 76
COPOLYMERS BASED ON CYCLOPENTADITHIOPHENE FOR ORGANIC PHOTOVOLTAICS
Myshkovskaya E.N., Ponomarenko S.A., Troshin P.A., Susarova S.D., Babenko S.D., Surin N.M.,
Muzafarov A.M .......................................................................................................................................... 77
MEAN FORCE POTENTIALS FOR ION PAIRS IN A BINARY SOLVENT MIXTURE
Odinokov A.V., Basilevsky M.V., Nikitina E.A., Petrov N. Kh., Alfimov M.V ...................................... 78
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STUDY OF A POLYMER MATRIX INFLUENCE ON PHOTOCHROMISM OF SPIROPIRANES,
INSERTED BY DIFFUSION FROM SOLUTIONS
Optov V.A., Ait A.O., Barachevsky V.A., Berlin A.A., Sabsai O.Yu ...................................................... 79
FORMATION AND DISSOCIATION OF SEMICONDUCTOR QUANTUM DOT / DYE MOLECULE
COMPLEXES
Orlova A.O., Toporova Yu.A., Maslov V.G., Fedorov A.V., Baranov A.V ............................................. 80
ATOMIC FORCE MICROSCOPY STUDY OF J-AGGREGATE NANOSTRUCTURES
Perelygina O.M., Prokhorov V.V., Lypenko D.A., Mal’tsev E.I., Vannikov A.V., Vannikov A.V.,
Vannikov A.V ............................................................................................................................................ 81
NEW EUIII AND TBIII HEXAFLUOROACETYLACETONATES WITH BIDENTATE O-DONOR
LIGANDS: SYNTHESIS, STRUCTURE AND OPTICAL PROPERTIES
Pleshkov D.N., Eliseeva S.V., Lyssenko K.A., Lepnev L.S., Kotova O.V., Kuzmina N.P ...................... 82
SYNTHESIS AND OPTICAL PROPERTIES OF HIGHLY LUMINESCENT CdS QUANTUM DOTS
Raevskaya A.E., Grodzyuk G.Ya, Stroyuk A.L., Kuchmiy S.Ya .............................................................. 83
STARLIKE OLIGOTHIOPHENESILANES FOR PHOTOVOLTAIC APPLICATIONS
Shumilkina E.A., Ponomarenko S.A., Troshin P.A., Hakina E.A., Surin N.M., Muzafarov A.M ............ 84
SYNTHESIS AND PHOTOLUMINESCENT PROPERTIES OF SOME LANTHANIDE COMPLEXES
(LN = Eu3+, Gd3+, Tb3+, Lu3+) WITH ORTHO-SUBSTITUTED PHOSPHORYLPHENOLS
Shuvaev S.V., Kotova O.V., Lepnev L.S., Kuzmina N.P., Baulin V.E., Tsivadze A.Yu ......................... 85
A NEW TECHNIQUE TO FABRICATE DIFFRACTIVE OPTICAL ELEMENTS ON THE BASIS OF
PERMOLECULAR STRUCTURES
Solovjev V.S., Volkov A.V., Rasshchepkina N.A ..................................................................................... 86
POLYMER/NANOCARBONS COMPOSITE MATERIALS FOR PHOTONICS
Spitsina N.G., Lobach A.S., Kaplunov M.G .............................................................................................. 87
DESIGNING FULLERENE/POLYMER BULK HETEROJUNCTION SOLAR CELLS WITH
ADVANCED ACTIVE LAYER MORPHOLOGIES
Susarova D.K., Troshin P.A., Babenko S.D., Lyubovskaya R.N., Razumov V.F ..................................... 88
PHOTODISSOCIATION OF COMPLEXES OF QUANTUM DOT/ORGANIC MOLECULES
EMBEDDED IN THIN POLYMER FILMS
Ushakova E.V., Orlova A.O., Baranov A.V .............................................................................................. 89
SERS, SPECTROPHOTOMETRY AND AFM STUDY OF PHOTOCHROMISM OF SPIROCYCLIC
COMPOUNDS ON NANOSTRUCTURED METAL FILMS
Vasilyuk G.T., Maskevich S.A., German A.E., Sveklo I.F., Lukyanov B.S., Ageev L.A ........................ 90
DYNAMICS OF PHOTOPROCESSES IN NOVEL BIFUNCTIONAL
SALICYLIDENEIMINOSPIRONAPHTHOXAZINES
Zaichenko N.L., Levin P.P., Mardaleishvili I.R., Shiyonok A.I., Kol’tsova L.S., Os’kina O.Yu., Tatikolov
A.S ............................................................................................................................................................. 91
PHOTOLUMINESCENCE KINETICS OF (ZINC)TETRAPHENYLPORPHYRIN-FULLERENE
CHARGE-TRANSFER COMPLEXES
Zakharova I.B., Ermolaeva G.M., Kvyatkovskii O.E., Belyakov L.V ...................................................... 92
PHOTOCHEMICAL PROCESSES IN SELF-ORGANIZED MULTIPORPHYRIN COMPLEXES
Zenkevich E.I., Sagun E.I., Knyukshto V.N., Von Borczyskowski C ....................................................... 93
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SYMPOSIUM “MOLECULAR PHOTONICS” Dedicated to Academician A.N.Terenin .. 94
ORALS ................................................................................................................94
INTERMOLECULAR INTERACTIONS AND PHOTOPROCESSES IN MOLECULAR SYSTEMS
Artyukhov V.Ya., Mayer G.V. ..................................................................................................................... 94
AN EFFECT OF THE THIRD COMPONENT ON THE LUMINESCENCE OF THE NANO-SIZED
NAPHTHALENE – CYCLODEXTRIN COMPLEXES
Avakayn V.G., Nazarov V.B., Vershinnikova T.G., Rudyak V.Y., Alfimov M.V. ........................................ 95
PHOTOCHROMIC NANOPARTICLES: PROPERTIES AND APPLICATIONS
Barachevsky V.A. ....................................................................................................................................... 96
PHOTONIC MOLECULAR LOGIC GATES
Budyka M.F. ............................................................................................................................................... 97
EFFECT OF SOLVENT POLARITY ON THE PRIMARY PHOTOPROCESSES OF CYANINE DYES
Chibisov A.K. ............................................................................................................................................. 98
PHOTONICS OF HEMOGLOBIN AND MYOGLOBIN ACTIVE CENTERS
Dzhagarov B.M., Lepeshkevich S.V. ........................................................................................................ 99
ACTIVITY AND SELECTIVITY OF PHOTOCATALYSTS
Emeline A.V. ............................................................................................................................................. 100
TETRAPHENYLPORPHYRIN DERIVATIVES STRUCTURE AND MOLECULE SURROUNDINGS
DEPENDING ON LUMINESCENT CHARACTERISTICS
Ermolina E.G., Kuznetsova R.T., Gadirov R.M., Mayer G.V., Korovin Yu.V., Semenishin N.N., Rusakova
N.V. .......................................................................................................................................................... 101
SPACE RADIATION IMPACT ON PREBIOTIC SYNTHESIS AND STABILITY OF BIOORGANIC
MOLECULES: COMPARATIVE STUDY
Gontareva N.B., Kuzicheva E.A. .............................................................................................................. 102
INTENSITIES OF IR BANDS OF SURFACE OH GROUPS OR OF THE C-H STRETCHING BANDS
OF ADSORBED MOLEQULES - A NEW SPECTRAL CRITERION OF ACTIVATION OF
CHEMICAL BONDS IN HETEROGENEOUS ACID CATALYSIS VIA THEIR POLARIZATION
Kazansky V.B., Subbotina I.R. ................................................................................................................. 103
THE EVOLUTION OF PHOTOCHEMICALLY GENERATED RADICAL PAIRS IN GLASSY
POLYMERS: RECOMBINATION FEATURES IN MACROMOLECULAR NANOREACTORS
Khavina E.Yu., Ivanov V.B. ...................................................................................................................... 104
PHOTOSTIMULATED ELECTRON TRANSFER IN STRUCTURES OF MUTATIONALLY
MODIFIED REACTION CENTERS FROM PHOTOSYNTHETIC BACTERIA
Kotelnikov A.I., Medvedev E.S., Goryachev N.S., Barinov A.V., Stuchebrukhov A.A., Ortega J.M. ....... 105
LUMINESCENCE TECHNIQUE IN THE STUDY OF BIOLOGICAL PROPERTIES OF FULLERENE
BASED HYBRID NANOSTRUCTURES
Kotelnikova R.A., Mishchenko D.V., Zhokhova D.A., Barinov A.V., Rybkin A.Yu., Goryachev N.S.,
Bogdanov G.N., Grigoriev V.V., Romanova V.S., Kotelnikov A.I. .......................................................... 106
PHOTONICS OF SINGLET OXYGEN DIMOLS AND MONOMOLS: RESULTS OF
PHOTOCHEMICAL AND LUMINESCENCE STUDIES
Krasnovsky A.A. ....................................................................................................................................... 107
DFT MODELLING OF ADENINE STACKING DIMERS IN WATER
Krauklis I.V., Chizhov Yu.V., Rapoport V.L. ........................................................................................... 108
MODELING OF EVOLUTIONARY PRIMITIVE ENERGY CONVERTER AND MOLECULAR
DEVICES BASED ON THE ACTIVITY OF PHOTOEXCITED FLAVINS
Kritsky M.S. .............................................................................................................................................. 109
ENERGY TRANSFER IN THE MOLECULAR SYSTEMS NEAR DIELECTRIC AND METAL
SURFACES
Kucherenko M.G., Chmereva T.M., Kislov D.A. ..................................................................................... 110
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COOPERATIVE PROCESSES OF ANTI-STOCKES LUMINESCENCE EXCITATION IN
CRYSTALS WITH ADSORBED ORGANIC DYE MOLECULES
Kvashnina N.V., Ovtchinnikov O.V., Latyshev A.N., Klinskikh A.F., Smirnov M.S., Suvorova T.I. ........ 111
THE ROLE OF INTRINSIC POINT DEFECTS IN SPECTRAL SELF-SENSITIZATION OF WIDEBANDGAP OXIDE PHOTOCATALYSTS
Lisachenko A.A. ....................................................................................................................................... 112
TRIPLET ENERGY TRANSFER FROM d0 ORGANOMETALLICS TO UNSATURATED
HYDROCARBONS: RECENT RESULTS AND PERSPECTIVES
Loukova G.V., Smirnov V.A. .................................................................................................................... 113
SENSIBILIZED ANTI-STOCKES LUMINESCENCE MECHANISM IN CRYSTALLS WITH
ADSORBED METALORGANIC NANOSTRUCTURES
Ovtchinnikov O.V., Suvorova T.I., Kvashnina N.V., Smirnov M.S., Latyshev A.N., Minakov D.A., Shulgin
V.A. ........................................................................................................................................................... 114
LUMINESCENCE STUDY OF STABLE STACKING AGGREGATES OF NITRIC BASES OF
NUCLEIC ACIDS – THE CANDIDATES FOR ROLE OF FIRST GENETIC TEMPLATES
Rapoport V.L., Malkin V.M., Krauklis I.V., Maslova E.A., Goriuchko V.V. ........................................... 115
FTIR STUDY OF POROUS ICE FILMS
Rudakova A.V., Marinov I.L., Tsyganenko A.A. ...................................................................................... 116
THE PRODUCTS AND MECHANISMS OF PHOTOCHEMICAL TRANSFORMATION OF OQUINONES
Shurygina M.P., Kurskii Yu.A., Druzhkov N.O., Chesnokov S.A., Abakumov G.A. ................................. 117
MESO-SUBSTITUTED POLYMETHINE DYES AS EFFICIENT SPECTRAL-FLUORESCENT
PROBES FOR BIOMACROMOLECULES
Tatikolov A.S., Akimkin T.M., Kashin A.S. ............................................................................................... 118
PHOTOACTIVATED TEMPLATES IN PREBIOTIC EVOLUTION PROCESSES
Telegina T.A., Kolesnikov M.P., Vechtomova Yu.L., Kritsky M.S. .......................................................... 119
ADVANCES IN SPECTRAL STUDIES OF SURFACE PHENOMENA
Tsyganenko A.A. ....................................................................................................................................... 120
POSTERS..........................................................................................................121
BACTERIORHODOPSIN-CONTAINING MULTILAYER STRUCTURES AS A MEDIUM FOR
BIOMOLECULAR NEURONET DEVICES OF PHOTONICS
Adamov G.E., Adamova D.A., Grebennikov E.P., Kurbangaleev V.R ................................................... 121
PROTONATION EFFECT AND SPECTRAL PROPERTIES OF PHOTOCHROMIC COMPOUNDS
Ait A.O., Barachevsky V.A., Gorelik A.M., Kobeleva O.I ..................................................................... 122
SPECTRAL-FLUORESCENT STUDY OF THE INTERACTION OF THE POLYMETHINE DYE CY2
WITH DNA AND HYALURONIC ACID
Akimkin T.M., Tatikolov A.S., Yarmoluk S.M ....................................................................................... 123
DFT SIMULATION OF PHOTOCATALYTIC NO REDUCTION BY СО ON Ti8O16 NANOCLUSTER
Andreev A.S., Chizhov Yu.V .................................................................................................................. 124
RELAXATION OF HIGH-LYING EXITED ELECTRONIC STATES OF POLYPYRIDYL RU(II)
COMPLEXES AND ITS RELATION TO SYMMETRY OF MOLECULAR STRUCTURE AND/OR
ENVIRONMENT
Artemyeva E.S., Litke S.V ....................................................................................................................... 125
2D-STRUCTURE EVIDENCE ON THE SURFACE OF SELF-SENSITIZED ZnO PHOTOCATALYST
Basov L.L., Lisachenko A.A ................................................................................................................... 126
PHOTOPHYSICAL PROCESSES IN CATIONS OF THIACARBOCYANINE DIMERS
Bazyl O.K., Artyukhov V.Ya., Mayer G.V ............................................................................................. 127
THE STRUCTURE AND PHOTOPHYSICAL PROCESSES IN SYMMETRIC POLYMETHINE DYES
Bazyl O.K., Artyukhov V.Ya., Svetlichnyi V.A., Ishchenko A.A .......................................................... 128
9
SHORT AND LONG-RANGE ORDER EFFECT ON RESONANCE ENERGY TRANSFER
Bodunov E.N ............................................................................................................................................ 129
THE LIQUID CRYSTAL COMPOSITES CONTAINING AN IMPURITY OF FLUORESCENT CdSe
NANORODS
Danilov V.V., Baranov A.V., Elyashevich G.K., Orlova A.O., Utkina N.A., Khrebtov A.I .................. 130
INVESTIGATION OF SPECTRAL PROPERTIES OF ISOXAZOLE DERIVATIVES CONTAINED
PHOTOCHROMIC LABEL
Demina O.V., Laptev A.V., Belikov N.E., Lukin A.Yu., Zemtsov R.V., Varfolomeev S.D., Khodonov A.A. 131
HETEROGENEOUS PHOTOCATALYSIS BY ZINС PHTHALOCYANINE DERIVATIVES FOR
PHENOLS OXIDATION
Fedorova T.M., Petrova E.G., Derkacheva V.M., Butenin A.V., Kaliya O.L ......................................... 132
SPECTRAL-LUMINESCENT AND LASING PROPERTIES OF THE SOME SUBSTITUTED OF
COUMARIN
Gadirov R.M., Kopylova T.N., Samsonova L.G., Nikonov S.Yu., Logis A.G ....................................... 133
NEW RADICAL MECHANISM OF PORPHYRIN PHOTOSENSITIZED DESTRUCTION OF
BIOLOGICAL MEMBRANES
Gurinovich V.V., Vorobey A.V., Tsvirko M.P ........................................................................................ 134
METHOD OF NONDESTRUCTIVE READ-OUT OF INFORMATION
Japaridze K., Devadze L., Maisuradze D., Sepashvili N ......................................................................... 135
INVESTIGATION OF THE PHOTOCHROMIC BEHAVIOUR OF THE RETINAL PROTEIN
CHROMOPHORE MODELS
Khodonov A.A., Laptev A.V., Lukin A.Yu., Belikov N.E., Zemtsov R.V., Zvezdin K.V., Shvets V.I.,
Barachevsky V.A., Varfolomeev S.D., Demina O.V .............................................................................. 136
INTERACTION OF CYCLOTETRAPYRROL COMPOUNDS WITH NANOPOROUS XEROGELS
AND OPTICAL RADIATION OF DIFFERENT INTENSITY
Kuznetsova R.T., Ermolina E.G., Telminov E.N., Mayer G.V., Arabei S.M., Pavich T.A., Solovyov K.N.,
Kalashnikova I.P., Ivanova S.S ................................................................................................................ 137
THE INVESTIGATION OF THE NO PHOTOADSORPTION IN CO PRESENCE ON TiO2
HOMBIFINE N BY MEANS OF KINETIC MASS-SPECTROMETRY AND THERMOPROGRAMMED DESORPTION SPECTROSCOPY
Laptenkov D.V., Mikhaylov R.V ............................................................................................................. 138
DIFFUSE REFLECTANCE SPECTROSCOPY FOR INVESTIGATION OF GAS-SURFACE
INTERACTIONS ON WIDE-BANDGAP OXIDES
Lisachenko A.A ....................................................................................................................................... 139
PHOTOINDUCED OXYGEN ISOTOPE EQUILIBRATION ON TiO2-X SURFACE UNDER VISIBLE
LIGHT IRRADIATION
Lisachenko A.A., Mikhaylov R.V., Titov V.V ........................................................................................ 140
EFFECTS OF DONOR STRUCTURE ON TRIPLET ENERGY-TRANSFER FROM AMINES TO
ALKENE IN SOLUTION
Loukova G.V., Lukov A.V., Smirnov V.A .............................................................................................. 141
ENERGY TRANSFER IN MOLECULES AND MOLECULAR SYSTEMS
Mayer G.V., Artyukhov V.Ya ................................................................................................................. 142
PROBE PHOSPHORESCENCE AND TRIPLET-TRIPLET ENERGY TRANSFER IN THE STUDY OF
CONFORMATIONAL CHANGES IN THE PROTEINS
Melnikov A.G., Kochubey V.I., Pravdin A.B., Naumova E.V., Dyachuk O.A., Melnikov G.V ............ 143
COMBINED KINETIC, UV-VIS, FTIR AND TPD STUDY OF THE PHOTOCATALYTIC NO
REDUCTION BY CO ON TiO2
Mikhaylov R.V., Lisachenko A.A., Shelimov B.N., Martra G., Coluccia S., Che M ............................. 144
MATHEMATICAL SIMULATION OF STRATEGY FOR THE CONTROL OF EXCITED-STATE
INTRAMOLECULAR REVERSIBLE PROTON TRANSFER IN THE MULTIPARAMETRIC
FLUORESCENCE PROBES
Morozov V.A ........................................................................................................................................... 145
10
PREPARATION OF MAGNESIUM PHTHALOCYANINE NANOCRYSTALS
Nadolinskaya S.S., Meshkov A.M., Maslov V.G., Korotkov V.I ........................................................... 146
PHOTOCHEMICAL TRANSFORMATIONS OF CHALCONE PODANDS IN THE CRYSTALS AND
SOLUTIONS
Ovchinnikova I.G., Fedorova O.V., Druzhinin A.V., Rusinov G.L., Charushin V.N ............................. 147
TWO-PHOTON PHOTOPROCESSES IN MOLECULAR SYSTEMS
Plotnikov V.G., Smirnov V.A., Alfimov M.V ......................................................................................... 148
FTIR STUDY OF METHANE INTERACTION WITH OXIDE ADSORBENTS
Poretskiy M.S., Tsyganenko A.A ............................................................................................................ 149
LUMINESCENT INVESTIGATION OF ACRIDINE HOMO-CONJUGATED COMPLEX
Rozhkova J.A., Gurinov A.A., Lesnichin S.B., Shenderovich I.G., Maslov V.G., Korotkov V.I ........... 150
PROTONATED NITROGEN-CONTAINING AROMATIC MOLECULES. SPECTROSCOPIC
INVESTIGATION
Rozhkova J.A., Gurinov A.A., Lesnichin S.B., Shenderovich I.G., Maslov V.G., Korotkov V.I ........... 151
ETHYLENE PHOTOPOLYMERIZATION ON ZEOLITE NA–ETS-10: IR SPECTROSCOPIC STUDY
Rudakova A.V., Lobo R.F., Ryabchuk V.K., Bulanin K.M .................................................................... 152
PHOTO-OZONOLYSIS OF CHLORINATED ETHENES AND HYDROGEN CYANIDE ON WATER
ICE FILMS
Rudakova A.V., Marinov I.L., Tsyganenko A.A ..................................................................................... 153
THE EFFICIENCY OF UV STIMULATED FORMATION OF ACTIVE CENTERS AT THE
SURFACE OF MICRO- AND NANO-DISPERSED ZRO2 PHOTOCATALYSTS
Ryabchuk V.K., Emeline A.V., Kataeva G.V., Kuzmin G.N., Sheremetyeva N.V ................................ 154
DECAY TIME OF ACTIVE SURFACE CENTERS ON WIDE BAND GAP METAL OXIDES
Ryabchuk V.K., Emeline A.V., Kataeva G.V., Sheremetyeva N.V ........................................................ 155
STRUCTURE AND PHYSICO-CHEMICAL PROPERTIES OF PHOTOACTIVE
SUPRAMOLECULAR SYSTEMS BASED ON CROWN-CONTAINING OLIGOTHIOPHENE
DERIVATIVES
Selector S.L., Arslanov V.V., Fedorova O.A., Lukovskaya E.V., Bobyleva A.V., Tarasova N.A., Fedorov
Y.V., Raitman O.A., Anisimov A.V., Anisimov A.V ............................................................................. 156
DETERMINATION OF MAGNETIC-DIPOLE TRANSITION 5D0 – 7F1 PURITY IN EUROPIUM
CHLORIDE LUMINESCENCE IN SOLUTION BY ENERGY TRANSFER TO DYES
Shakhverdov T.A ..................................................................................................................................... 157
COMPARATIVE STUDY OF SPECTRAL PROPERTIES OF CROSS-CONJUGATED
BISAMINOKETONES AND DINITRILES
Shvedova L.A., Tatikolov A.S., Krasnaya Zh.A ..................................................................................... 158
DECAY KINETICS OF TRIPLET STATES AND RADICALS OF FLAVINS IN THE BOVINE LENS
STUDIED BY LASER FLASH PHOTOLYSIS
Tatikolov A.S., Levin P.P., Sultimova N.B., Panova I.G ........................................................................ 159
FLUORESCENCE RESONANCE ENERGY TRANSFER AND COMPLEX FORMATION BETWEEN
CYANINE DYES AND DNA
Tatikolov A.S., Pronkin P.G .................................................................................................................... 160
REACTIONS OF PHOTOINDUCED AND THERMAL RECOORDINATION IN OPTICAL
MOLECULAR SENSORS
Ushakov E.N., Dmitrieva S.N., Vedernikov A.I., Kuz’mina L.G., Freidzon A.Ya., Alfimov M.V.,
Gromov S.P .............................................................................................................................................. 161
INFLUENCE OF THE SOLVENT ON THE RADIUS OF ELECTRON-EXCHANGE INTERACTIONS
OF d0 METAL COMPLEXES WITH CYCLOPENTADIENE
Vasiliev V.P., Loukova G.V., Smirnov V.A ............................................................................................ 162
FTIR EVIDENCE FOR LEWIS ACIDITY INDUCED BY ADSORPTION
Voronina K.V., Tsyganenko A.A ............................................................................................................ 163
11
SYMPOSIUM “FUNDAMENTAL PRINCIPLES OF NANOPHOTONICS” .............164
ORALS ..............................................................................................................164
OBTAINING, PROPERTIES AND PERSPECTIVES OF COLLOIDAL QUANTUM DOTS
Brichkin S.B., Spirin M.G., Nikolenko D.Yu., Gak V.Yu., Razumov V.F. ................................................ 164
SEMICONDUCTOR QUANTUM DOT MOLECULE PHOTOLUMINESCENCE MEDIATED BY
INCOHERENT REVERSIBLE ENERGY TRANSFER
Fedorov A.V., Baranov A.V., Kruchinin S.Yu., Savelyeva A.V., Mukhina M.V. ...................................... 165
MOLECULAR DESIGN OF LIGHT-SENSITIVE NANOSIZED SYSTEMS BASED ON
UNSATURATED AND MACROCYCLIC COMPOUNDS
Gromov S.P., Ushakov E.N., Vedernikov A.I., Kuzmina L.G., Alfimov M.V. .......................................... 166
AOT/WATER/HEXANE REVERSE MICELLES AS “MICELLAR SIEVES” FOR CYANINE DYE JAGGREGATES
Ivanchikhina A.V., Nikolenko L.M. .......................................................................................................... 167
DELAYED FLUORESCENCE ANNIHILATION KINETICS CHANGE BY RECONSTRUCTION OF
POLYMERIC CHAIN STRUCTURE IN SOLID SORBENT CAVITIES AND ON NANOPARTICLE
SURFACES
Kucherenko M.G., Izmodenova S.V., Kruchinin N.Y. .............................................................................. 168
THE FEATURES OF THE RECOMBINATION PROCESSES INTO THE PYROLYTIC CdS FILMS
Maiorova T.L., Klyuev V.G., Pham Thi Hai M., Bikovskaya V.S. ........................................................... 169
LUMINOPHORE-CONTAINING MONODISPERSE POLYMERIC NANOPARTICLES: DESIGN,
SELF-ASSEMBLING, AND APPLICATION FOR CHEMISENSORICS
Menshikova A.Yu., Shevchenko N.N., Evseeva T.G., Yakimansky A.V., Sazhnikov V.A., Koshkin A.V.,
Alfimov M.V. ............................................................................................................................................ 170
MOLECULAR DYNAMICS SIMULATIONS OF AN AOT REVERSE MICELLES SELF-ASSEMBLY
Nevidimov A.V. ......................................................................................................................................... 171
SUPRAMOLECULAR ENSEMBES OF Ru(II) PHTHALOCYANINATE, NONLINEAR OPTICAL
AND PHOTOREFRACTIVE PROPERTIES
Pereshivko L.Ya., Vannikov A.V., Grishina A.D., Zolotarevsky V.I., Gorbunova Yu.G., Enakieva Yu.Yu.,
Krivenko T.V., Savelyev V.V., Tsivadze A.Yu. .......................................................................................... 172
POLARISATION ANISOTROPY OF SINGLE-CRYSTAL OPAL FILMS
Plekhanov A.I., Chubakov V.P., Chubakov P.A. ...................................................................................... 173
LASING IN PHOTONIC CRYSTAL OPAL FILMS AND HETEROSTRUCTURES
Plekhanov A.I., Kuchyanov A.S. .............................................................................................................. 174
POLARIZATION AND ORIENTATION ANISOTROPY OF RESONANT OPTICAL PROPERTIES IN
POLYMER 3D PHOTONIC CRYSTALS
Selkin A.V., Fedotov V.G., Ukleev T.A., Menshikova A.Yu., Shevchenko N.N. ....................................... 175
NANOPHOTONICS OF FULLERENE SOLUTIONS
Sheka E.F., Razbirin B.S. ......................................................................................................................... 176
NANOPHOTONICS IN PRINTING AND PACKAGING. DIGITAL AND ANALOGUES IMAGES
TREATMENT AND PRODUCING
Sherstiuk V., Molodid S. ........................................................................................................................... 177
PHOTOPHYSICAL AND PHOTOCHEMICAL EFFECTS IN ASSEMBLIES OF NANOPARTICLES
IMMOBILIZED ON METAL OR DIELECTRIC SUBSTRATES AND MOLECULAR TEMPLATES
Strekal N.D., Maskevich S.A. ................................................................................................................... 178
SEMICONDUCTOR PHOTOCATALYSIS ON THE NANOSCALE: STATE-OF-THE-ART AND
PERSPECTIVES
Stroyuk A.L., Kuchmiy S.Ya., Kryukov A.I., Pokhodenko V.D. ................................................................ 179
12
COFLUORESCENCE OF DYES IN NANOSTRUCTURES OF METAL ION COMPLEXES WITH
DIKETONES
Sveshnikova E.B., Ermolaev V.L., Dudar S.S. ......................................................................................... 180
NANOSIZE STRUCTURES IN POLYMER BASED SOLAR CELLS
Tameev A.R., Vannikov A.V. .................................................................................................................... 181
SPATIAL DISPERSION AND LOCAL FIELD EFFECTS FOR SEMI-INFINITE MEDIA WITH
EMBEDDED NANOPARTICLES
Tishchenko A.A., Ryazanov M.I., Strikhanov M.N. .................................................................................. 182
ORDERED STRUCTURES ON THE BASIS OF SELF-ASSEMBLY OF CdSe AND Au PARTICLES
Zaporohzets M.A., Nikolaichik V.I., Volkov V.V., Baranov D.A., Dembo К.А., Syl’yanov S.N., Zhigalina
O.M., Gubin S.P., Avilov A.S., Khodos I.I. .............................................................................................. 183
OPTICAL PROPERTIES OF NANO-STRUCTURED POLYMER LIQUID CRYSTAL COMPOSITES
Zharkova G.M., Petrov A.P., Khachaturyan V.M. ................................................................................... 184
POSTERS..........................................................................................................185
DIFFERENTIAL PARAMETERS OF ORGANIC PHOTOELEMENT WITH BULK
HETEROJUNCTION
Babenko S.D., Moskvin Yu.L., Troshin P.A., Balakai A.A. ................................................................... 185
A COMPARISON OF THE PHOTOPHYSICAL PROPERTIES OF CADMIUM CHALCOGENIDE
NANOPARTICLES SYNTHESIZED BY VARIOUS METHODS
Gak V.Yu., Nikolenko D.Yu., Brichkin S.B., Razumov V.F., Zaporozhets M.A ................................... 186
INVESTIGATION ON THE POSSIBILITY OF COVERING CYANINE DYE J-AGGREGATES WITH
SILICA SHELLS
Ivanchikhina A.V ..................................................................................................................................... 187
THE LUMINESCENCE OF POLYMER COMPOSITE MATERIALS WITH CdS NANOPARTICLES
Kochubey V.I., Konyukhova Ju.G., Zabenkov I.V .................................................................................. 188
PHOTOELECTRIC NONLINEAR OPTICAL AND PHOTOREFRACTIVE PROPERTIES OF
COMPOSITES FROM POLYVINYLCARBAZOLE AND SINGLE-WALLED CARBON
NANOTUBES
Krivenko T.V., Pereshivko L.Ya., Grishina A.D., Savelyev V.V., Rychwalski R.W., Vannikov A.V .. 189
ZIRCONIA NANOPARTICLES AS NEW MODEL MATERIAL FOR NANOPHOTONICS: EFFECTS
OF SELF-ORGANIZATION
Lybenets V.A., Gorban O.A., Lyubchanskii I.L., Danilenko I.A., Konstantinova T.E ........................... 190
LIGHT EMITTING AND OPTICAL PROPERTIES OF SILICON-RICH SILICON NITRIDE AND
SILICON-RICH SILICON OXIDE FILMS
Nikitin T., Khriachtchev L., Novikov S., Rasanen M ............................................................................. 191
CLUSTERING OF CADMIUM TELLURIDE QUANTUM DOTS IN A WATER SOLUTION IN THE
PRESENCE OF METAL IONS: THE ABSORPTION AND LUMINESCENT ANALYSIS
Orlova A.O., Savelyeva A.V., Mukhina M.V., Maslov V.G., Baranov A.V., Fedorov A.V .................. 192
SILICA NANOPARTICLES MODIFIED BY PYRYLOCYANINE DYE WITH EFFECTIVE
LUMINESCENT RESPONSE
Orlova N.A., Kargapolova I.Yu., Shelkovnikov V.V., Plekhanov A.I .................................................... 193
COMPARISON STUDY OF THE NONLINEAR OPTICAL PROPERTIES OF MOLECULAR J- AND
H- AGGREGATES IN THIN SOLID FILMS
Plekhanov A.I., Gorkovenko A.I., Orlova N.A., Simanchuk A.E., Shelkovnikov V.V .......................... 194
LARGE ANGULAR DISPERSION EXPERIENCED BY A LIGHT BEAM IN PASSING THROUGH
THE BOUNDARY OF A GLASS SUBSTRATE-PHOTON CRYSTAL
Plekhanov A.I., Zabolotskii A.A., Kuchyanov A.S ................................................................................. 195
13
PHOTONIC BAND GAP IN PHOTONIC CRYSTAL FORMED BY THE HOLOGRAM
Shcheulin A.S., Angervaks A.E., Kupchikov A.K., Ryskin A.I .............................................................. 196
STRUCTURAL ASPECT OF NANOPHOTONICS OF FULLERENE SOLUTIONS
Sheka E.F., Razbirin B.S., Starukhin A.N., Nelson D.K., Degunov M.Yu., Troshin P.A., Lyubovskaya
R.N., Fazleeva V.P., Gubskaya V.P., Nuretdinov I.A ............................................................................. 197
MONODISPERSE POLYMERIC NANOPARTICLES MODIFIED WITH CYCLODEXTRINS AND
DYES
Shevchenko N.N., Menshikova A.Yu., Noskova I.V., Shabsels B.M., Yakimansky A.V ...................... 198
RELATIONSHIP BETWEEN WATER VAPOR PRESSURE OF REVERSE MICELLAR SYSTEM
AND REVERSE MICELLES SIZE DISTRIBUTION
Tovstun S.A., Razumov V.F .................................................................................................................... 199
THE STUDY OF ENDOTAXIAL NANOSTRUCTURIZATION OF POLY(3HEXYLTHIOPHENE)/FULLERENE COMPOSITE BY LIGHT-INDUCED ESR SPECTROSCOPY
Yudanova E.I., Krinichnyi V.I ................................................................................................................. 200
ELECTROOPTICAL PROPERTIES OF POLARIZATION HOLOGRAPHY GRATINGS IN
POLYMER DISPERSED LIQUID CRYSTALS
Zharkova G.M., Streltsov S.A., Petrov A.P., Khachaturyan V.M ........................................................... 201
INDEX ....................................................................................................................................... 202
14
INTERNATIONAL CONFERENCE
“ORGANIC NANOPHOTONICS”
ORALS
LINEAR AND NONLINEAR OPTICAL PROPERTIES OF UV-INDUCED
GOLD NANOPARTICLES IN POLYMERIC MATRICES
A.V. Afanasiev1, A.P. Alexandrov1, A.E. Mochalova2, L.A. Smirnova2,
N.M. Bityurin1
1 - IAP RAS, 330 Department, Nizhniy Novgorod, Russia
2 - NNSU, Nizhniy Novgorod, Russia
ava@ufp.appl.sci-nnov.ru
Over the last decade, there has been a growing scientific interest in searching novel
nanostructured materials all over the world. We report investigation of linear and nonlinear
optical properties of UV-induced gold nanoparticles in polymeric matrices. Unlike common
methods of structured materials preparation with using incorporating steady nanosized objects
into polymer matrix, we represent new materials, where structured domains are formed by
irradiation initially nonstructured material in specific spectral band (UV). This fact opens the
opportunity of varying shape of growing structures, setting necessary properties in obtained
regions with new optical properties. Moreover, it could be done locally with focused laser beam.
Our experimental setup based on Er-doped fiber laser generating 100 fs pulses on wavelength
1570 nm. Highly sensitive method based on spectrally resolved two-beam coupling technique
was used for detection of optical nonlinearity in thin polymeric films in IR spectral range. The
main idea of this method of measurements is to mix two beams with high and low intensity in
focal area. Intensive femtosecond pulse leads to refractive index addition. Weak pulse gets
additional phase shift, so its spectrum changes. Thus, spectral analysis allows getting information
about nonlinear optical properties of studied media. The nonlinearity activation time could be
measured with using time delay between pump and probe femtosecond laser pulses. High figures
of nonlinear refractive index and two-photon absorption coefficient were obtained in studied
materials. Further studies will optimize the composition and conditions of preparation for higher
optical nonlinearities.
Linear refractive index changes were demonstrated while phase diffraction gratings were
studied. Good efficiency of diffraction transformation was shown with visible and IR laser
radiation. More complicated structures were recorded in modified media. These structures lead
to multiplexing of laser beam.
High damage threshold of studied materials, precise localization of modified areas, low cost and
simple technique of preparation, high stability and longevity are additional advantages among
other advanced non-linear optical materials. Obtained 3D-structures deep inside of samples are
safe of surface damage. Materials have low optical losses in wide spectral range, so they could
be widely adopted in real devices.
15
FEMTOSECOND NANOPHOTONICS OF GOLD AND SILVER
CLUSTERS PHOTODEPOSITED ON CRYSTALLINE
AND AMORPHOUS MESOPOROUS FILMS OF TiO2
A. Aiboushev, A. Astafiev, V. Nadtochenko, O.M. Sarkisov
N.N. Senenov Institute of Chemical Physics RAS, Moscow, Russia
aiboosh@gmail.com
Mesoporous films, composed from TiO2 nanoparticles can be used as a photocatalyst for light
to chemical energy conversion. Metal nanoparticles photodeposited on TiO2 surface can
improve catalytic properties of TiO2. The effects of electromagnetic field enhancement by
metallic nanoparticles could be the most important reason for dramatic increase of Raman
scattering cross section or for enhancement in luminescence spectroscopy. Luminescence of
gold and silver nanoparticles on titan dioxide nanoparticles of the mesoporous film is studied for
the case of crystalline and amorphous forms of TiO2. Ag and Au metal nanoparticles were
prepared on the porous TiO2 film by photodeposition technique. Such a system has three main
characteristic features: first, TiO2 nanoparticle size is about 25nm; second, the average distance
between metal nanoparticles is of order of several nm; third, size of metal nanoparticles is less
than 10nm.
Luminescence was registered under the two-photon excitation by femtosecond laser pulses of
Ti:sapphire laser at 800nm. It occurs that Ag/TiO2 and Au/TiO2 mesoporous films have high
concentration of bright luminescence points (hot spots) which reveal stability to degradation
under long illumination. Luminescence of the mesoporous film in range from 400 to ~750nm
(at 800nm pumping) means two-photon absorption in mesoporous film.
Mesoporous film has quite nonuniform hot spots distribution. Therefore there are some specific
nanoparticles configurations in the film which the most effectively enhance electromagnetic
field. Estimation of enhancement of hot spot luminescence in experiment is of order of 104. On
the other hand, the effect of two-photon absorption and further luminescence is proportional to
E 4 , where E is amplitude of electromagnetic field at wavelength of excitation. Therefore hot
spot field enhancement at wavelength of excitation (800nm) should be ≈ 4 104 = 10 .
Size, shape and geometry effects of Ag and Au nanoparticles studied by FDTD computer
simulation. Local plasmon resonance (LPR) position was found for dimmer , trimer and chain of
metal nanoparticles. LPR positions are in range 360-500nm and 500-650nm for silver and gold
nanoparticles respectively. TiO2 mesoporous film leads to several time higher absorption at
800nm (excitation wavelength). Local field enhancement of Ag/TiO2 and Au/TiO2 composites
was ~10 (coincides with estimation from experiment).
Dependence of luminescence intensity on excitation laser pulse polarization studied
experimentally for “hot spots” of mesoporous film. It occurred each “hot spot” luminescence
has different dependence on excitation laser pulse polarization which in accordance with model
of two-close nanoparticle.
Enhancement of Raman scattering of molecules deposited on Ag/TiO2 and Au/TiO2
mesoporous films was demonstrated for the case of Rhodamine B. Properties of Ag/TiO2 and
Au/TiO2 mesoporous films show its promising usage for single molecule spectroscopy and
biological objects visualization with high sensitivity.
16
DISSOCIATIVE LUMINESCENT SENSOR BASED
ON QUANTUM DOT / ORGANIC MOLECULE SYSTEM
A.V. Baranov, V.G. Maslov, A.O. Orlova, Yu.A. Toporova,
E.V. Ushakova, A.V. Fedorov, S.A. Cherevkov
St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
a_v_baranov@yahoo.com
Luminescent sensors comprising complex of semiconductor nanocrystal (quantum dot, QD) and
molecule are of great interest at present. Particularly they can be used for detection of different
metal ions in water solution. These sensors demonstrate changes of QD luminescence intensity
depending on concentration of analyte in probe. Usually, QD luminescence in QD/molecule
complexes is quenched by fluorescence resonant energy transfer (FRET) from QD to molecule.
In one type of sensors absorption spectrum of molecule is changed in presence of analyte
following reduction of overlapping integral and increasing of QD luminescence intensity [1]. In
other case increase of QD luminescence intensity results from the complex dissociation in
presence of the analyte [2].
We report results of study of dissociative luminescent sensor based on complex comprising
luminescent hydrophobic core/shell CdSe/ZnS QDs and 1-(2-pirydilazo)-2-naphtol (PAN)
molecules. PNG is known as an indicator of Co and Ni ions [3]. By means of absorptionluminescent analysis it was shown that in organic solutions QD and PAN form complex where
PAN is coupled with QD shell Zn ion by coordination bond. At QD size corresponding to
optimal value of the overlapping integral the QD luminescence is practically quenched. It was
found that PAN in some organic solutions or in thin polymer films is able to extract Co and Ni
ions from neighbouring water solution and forms complexes with them. It was also shown the
same takes place in case of QD/PAN complexes in organic solutions or thin polymer film. We
found that presence of Co or Ni ions in organic solution or film results in dissociation of the
QD/PAN complexes and formation stable complexes PAN with these metal ions. Importantly
dissociation of QD/PAN complexes is followed by appearance of QD luminescence which
intensity is proportional to concentration of the metal ions in analyzed water solution that can be
used in analytical purposes. We also discovered that stability of the QD/PAN complexes depends
on value of water solution pH and showed that this sensor can be used for pH measurements in
3-5 range. Finally, since application of the luminescence sensors presupposes optical excitation
of the luminescence, we present results of study of QD/PAN complex photodissociation in
polymer films.
1. Brogan L., Lui W., “Semiconductor nanocrystal complexes and methods of detecting
molecular interactions using same”, US patent 2007003948, 2007
2. Mogul R., “Luminescent nanosensor”, WO patent 2006083269, 2006.
3. D. Betteridge at all, Anal. Chem., vol. 35, No 6, pp. 729-733 (1963).
17
SELF-AGGREGATION OF LUMINESCENT SILICA NANOPARTICLES
IN AQUEOUS SOLUTIONS OF AMPHIPHILIC COMPOUNDS
AND SURFACTANTS
S.V. Fedorenko1, A.R. Mustafina1, O.D. Konovalova2, A.I. Konovalov1
1 - A.E. Arbuzov Institute of Organic and Physical Chemistry RAS, Kazan, Russia
2 - A.M. Butlerov Chemistry Institute, Kazan State University, Russia
svetlana.fedorenko@yahoo.com
Self-aggregation of nanoparticles is a key problem in nanochemistry. The unguided agglutination
restricts the use of nanoparticles as biomarkers and biosensors, while the directed selfaggregation sometimes is of great interest as a prerequisite for 3D nanostructured architechtures.
The present report introduces our recent studies of self-aggregation processes taking place in
aqueous dispersions of luminescent silica nanoparticles at various concentrations of amphiphilic
salts and surfactants. The silica coated Tb(III)-p-sulfonatothiacalix[4]arene (Tb(III)-TCAS)
nanoparticles (40±5 nm) both unmodified and modified by amino- and carboxy anchoring
groups were used as main building blocks. The analysis of conductometric, electrophoretic and
dynamic light scattering data of the abovementioned nanoparticles at the varied concentrations of
amphiphilic counter ions reveal the key
silica matrix
factors driving the nanoparticles selfaggregation. The presence of the ionised
groups on the particle surface is the main,
but not the only way of the nanoparticles
stabilization, which restricts them from
the agglutination. Covering of the
nanoparticles by ionic and non-ionic
surfactants double layer is another way to
prevent their unguided self-aggregation in
diluted solutions of surfactants. The
Tb(III)-TCAS
further
increase
of
surfactants
concentrations
prompts
the
selflayer or bi-layer
aggregation of nanoparticles. These
of surfactant
aggreagates can be separated from the
aqueous solutions by temperature induced
phase separation procedure. The advantages and drawbacks of the surfactant induced selfaggregation of nanoparticles for the development of 3D colloid architechtures is discussed.
Acknowledgements
We thank RFBR (grant N 07-03-00282) and BRHE REC 007 for financial support.
1. A.R. Mustafina, S.V. Fedorenko, O.D. Konovalova, A. Yu. Menshikova, N.N. Shevchenko,
S.E. Soloveva, A.I. Konovalov, I.S. Antipin, Langmuir, 25 ( 2009) 3146-3151.
18
INCOHERENT ENERGY TRANSFER IN QUANTUM DOTS:
TIME-DOMAIN LUMINESCENT SPECTROSCOPY
A.V. Fedorov, A.V. Baranov, S.Yu. Kruchinin, E.V. Ushakova,
A.V. Savelyeva, M.V. Mukhina
St.Petersburg State University of Information Technologies, Mechanics and Optics State
University of Information Technologies, Mechanics and Optics, Russia
a_v_fedorov@inbox.ru
The investigation of nonradiative energy transfer between pairs of spatially separated quantum
dots (QDs) is one of the most important problems in modern solid-state physics. In recent years,
this phenomenon in QD systems has been extensively studied both experimentally and
theoretically. This interest is stimulated by predicted future technological applications such as
luminescent markers and sensors [1], low-threshold lasers [2], cellular automata [3], and
quantum computers [4]. In addition, an ensemble of QDs is a good model for the detailed
investigation of the basic physics of nonradiative energy-transfer phenomena. Because of the
quantum size effect, one can generate a resonance condition between arbitrary electronic states
of the QD donor and QD acceptor by choosing quantum dots of a suitable size and shape. This
allows the investigation of the dependence of energy-transfer efficiency on the properties of the
electronic states involved in this process.
In present work based on our previous results [5] the theory of photoluminescence in
time-domain for semiconductor quantum dot molecule with the incoherent energy transfer is
developed. Using a two-band model and under the assumption that interaction between electrons
of the QD-donor of energy and QD-acceptor of energy is described by a screened Coulomb
potential, we calculate kinetics of the photoluminescence signals at pulse excitation. This
approach allows us to adequately consider the specific cases of short interdot distances and
dipole-forbidden transitions in the acceptor. We restrict our consideration to a case when the
energy transfer rate γ DA between QDs is well below the dephasing rate ΓDA for this transition,
i.e. we study the incoherent energy transfer. Both the reversible and irreversible regimes of
energy transfer have been investigated. First of them takes place if the intraband energy
relaxation rate γ A for QD-acceptor is equal in order of value or less than γ DA . In this case some
portion of the energy will come back from the QD-acceptor to the QD-donor. Second regime is
realized if γ A >> γ DA . Our results are of important for a better insight into physical processes in
one-, two-, and three-dimensional structures with enough close-packed arrangement of QDs, e.g.
in the quantum dot molecules, chains, rings, two- and three-dimensional arrays as well as the
dendrites based on QDs.
1. X. Michalet, F. F. Pinaud, L. A. Bentolila et al., Science 307, 538 (2005).
2. S. Noda, Science 314, 260 (2006).
3. A. Imre, G. Csaba, L. Ji et al., Science 311, 205 (2006).
4. S. Sangu, K. Kobayashi, A. Shojiguchi et al., Phys. Rev. B 69, 115334 (2004).
5. S.Yu. Kruchinin, A.V. Fedorov, A. V. Baranov et al., Phys. Rev. B 78, 125311 (2008).
19
THEORY OF OPTICAL NANO MANIPULATION
H. Ishihara1, T. Iida2, H. Ajiki3
1 - Osaka Prefecture University, Department of Physics and Electronics, Sakai, Japan
2 - Osaka Prefecture University, Research Institutes for the Twenty-First Century, Sakai, Japan
3 - Osaka University, Graduate School of Engineering, Suita, Japan
ishi@pe.osakafu-u.ac.jp
In spite of recent progress in optical manipulation techniques of small objects such as laser
tweezers and laser cooling, the manipulation of nanoscale objects by the radiation force is still
challenging in nanotechnologies.
The light-scattering cross section of nano particles is usually too small to exert enough force to
trap or move them. Recently, we have theoretically revealed that an electronically resonant
optical response causes a radiation force strong enough to manipulate nanoscale objects [1],
which opens the way to a new type of optical manipulation linked with quantum-mechanical
properties of nanoscale objects. For example, it would enable us to perform size-selective
manipulation of nanoparticles by using the mechanism that the resonant optical response of
quantum-mechanically confined electronic states is extremely sensitive to the particle size. In the
experiment demonstrated in the superfluid He, a preliminary result of size-selective manipulation
of quantum dots has been obtained [2].
In this talk, we introduce our theoretical proposal on nano optical manipulation and related
experimental results described above. We also discuss our latest theoretical results, such as those
on the manipulation of nanoscale objects by designed light fields [3], size selective manipulation
of carbon nanotubes [4], and the inter-particle radiation-induced force that would be useful for
the manipulation of collective motion of nanoscale objects [5][6].
[1] T. Iida and H. Ishihara: Phys. Rev. Lett. 90, 057403 (2003),
Also see Phys. Rev. Focus 11, Story 6, 11 Feb. (2003)
[2] K. Inaba, K. Imaizumi, K. Katayama, M. Ichimiya, M. Ashida, T. Iida, H. Ishihara,
and T. Itoh: phys. stat. solid. (b) 243, 3829 (2006).
[3] T. Iida, T. Yoshimizu, and H. Ishihara: phys. stat. sol. (c)6, 69 (2009)
[4] H. Ajiki, T. Ishikawa, T. Iida, and H. Ishihara phys. stat. sol. (c)6, 65 (2009)
[5] T. Iida and H. Ishihara: Phys. Rev. Lett. 97, 117402 (2006)
[6] T. Iida and H. Ishihara: Phys. Rev. B77, 245319 (2008)
Also see Phys. Rev. Focus 21, Story 21, 25 June (2008)
20
SILICON NANOPHOTONICS: PRESENT STATUS AND PERSPECTIVES
L. Khriachtchev
Laboratory of Physical Chemistry, University of Helsinki, Finland
leonid.khriachtchev@helsinki.fi
Photonics is a leading technology of this century, and developing this area based on silicon
technology promises revolutionary progress in optoelectronics. Integration of all optical
functions into silicon is a strong challenge, and Si nanocrystals (Si-nc) open a remarkable
perspective here.1
We present a series of experimental data on optical and structural characterization of Si-nc in
silica matrix. Raman spectroscopy characterizes the structure of Si-nc. Spectral filtering of
photoluminescence observed in these absorbing films allows measuring their optical properties.2
The 1.5-eV photoluminescence of these samples shows systematic correlations with the optical
and structural properties and chemical composition estimated by X-ray photoelectron
spectroscopy. Based on the obtained data, the light-emission mechanisms are discussed.3
Laser radiation can crystallize amorphous Si nanostructures embedded in silica, which also
changes the optical properties.4,5 Recently we have found that the laser effect on silicon
nanostructures in silica films can be done in small areas of submicron sizes, and this optical
change is detectable by camera photographs and by Raman scattering and transmission
measurements.6 The microscopic structure and hence the optical response are stable at very high
temperatures as it is demonstrated by prolonged furnace annealing at 1200 °C. The developed
methods provide optical data with high density and a very long retention times suitable for
extreme temperature conditions, which can be used for non-volatile storage.
The work was supported by the Academy of Finland through the Finnish Center of Excellence
“Computational Molecular Science” and the FinNano Project “Optical and Surface Properties
of Nanoparticles”. Cooperation with Sergei Novikov, Timur Nikitin, Olli Kilpelä, Jouko
Lahtinen, Rama Velagapudi, Markku Räsänen, Juha Sinkkonen, Claudio Oton, Daniel NavarroUrrios, Eero Haimi, and Lorenzo Pavesi is gratefully acknowledged.
1
Silicon Nanophotonics: Basic Principles, Present Status and Perspectives, edited by L.
Khriachtchev (World Scientific, 2008);
2
L. Khriachtchev et al. Appl. Phys. Lett. 83, 3018 (2003);
3
L. Khriachtchev et al. Appl. Phys. Lett. 94, 043115 (2009);
4
L. Khriachtchev et al. Appl. Phys. Lett. 86, 141911 (2005);
5
L. Khriachtchev et al. Appl. Phys. Lett. 88, 013102 (2006);
6
T. Nikitin et al. Appl. Phys. Lett. 94, 173116 (2009).
21
NOVEL NANOCOMPOSITE MATERIALS BASED ON
MESOMORPHIC GLASSES OF METAL ALKANOATES:
STRUCTURES AND NONLINEAR-OPTICAL PROPERTIES
G. Klimusheva1, Y. Garbovskiy1, S. Bugaychuk1, A. Tolochko1, T. Mirnaya2
1 - Institute of Physics NASU, Kiev, Ukraine
2 - Institute of General and Inorganic Chemistry NASU, Kiev, Ukraine
klimush@iop.kiev.ua
To demands of fast recording and processing of large amount of optical information we propose
novel nanocomposite materials, namely ordered mesomorphic glasses of metal alkanoates. The
salts of the metal-alkanoates form a smectic A mesophase by heating, which is easy subcooling
with creating the ordered mesomorphic glasses. The layered smectic A has the following
structure: electrostatic cation-anion layers and bi-layers of alkanoate chains. The mesomorphic
glasses are universal matrixes for many organic and inorganic nanoinclusions as well as for
nanosized crystals. We develop preparation technologies for several different cells based on
mesomorphic glasses, and investigate their structures by X-ray method and nonlinear optical
properties. Impulse laser technique is used for nonlinear optical experimental studies.
(1) Mesomorphic glasses on the base of La+3(C5H11COO)3 doped by organic dyes. Our
technology permits to introduce into the mesomorphic matrix the dyes with different molecular
structures (polymethine dyes of anion type, of cation type and neutral ones). Doped impurities do
not distort the structure of the mesomorphic glass as the impurity molecules are built up well
inside the matrix. It was shown that the doped impurities determine the nonlinear-optical
properties of the whole cells, but the matrix provides fast relaxation of the heat.
(2) Mesomorphic glasses of Co(II) alkanoates. We investigate the homological series CoCn+1,
where n=7,9,11 and the common structural formula is Co2+(CnC2nCOOH)-2.These cells are
colored, but we do not observe the nonlinear absorption effects. The recording of phase
dynamical grating is found in these cells. It was shown that the refractive index change is caused
by change of coordination states Co(II) at the action of laser radiation. Gigantic values of the
nonlinearity are obtained during this process, the diffraction efficiency can reach ~1% with the
cell thickness ~10-20 µm.
(3) The salts of the Cd alkanoates with nanoparticles of semiconductor CdS are synthesized for
the first time. On their base the mesomorphic glasses are prepared that contain nanosized crystals
CdS inside their electrostatic layers. Absorption and luminescent spectrums are investigated in
these novel materials.
We demonstrate that investigated novel materials posses high value of the optical nonlinearity,
they have fast times both for the recording and for the relaxation of holographic gratings. They
are perspective materials for creating high-speed telecommunication devices on their base.
22
ELECTROLUMINESCENCE OF ORGANIC MOLECULES
IN BLUE-GREEN AND RED RANGES OF THE SPECTRUM
T.N. Kopylova1, G.V. Mayer1, R.M. Gadirov1, K.M. Degtyarenko1,
A.V. Egorova2, N.S. Eremina1, A.V. Kukhto3, S.B. Meshkova2,
Z.M. Topilova2, V.F. Shul’gin4, L.G. Samsonova1
1 - Tomsk State University, Tomsk, Russia
2 - Physical Chemical Institute NASU, Odessa, Ukraina
3 - Institute of Physics NASB, Minsk, Belarus
4 - Tavriya National University, Simferopol, Ukraina
kopylova@phys.tsu.ru
The development and synthesis of organic V. F.4 molecules that can luminesce effectively in thin
films through which electric current flows remain urgent problems of organic electronics. This
work presents results of synthesis and investigation of photo- and electroluminescence of some
optical compounds of rare-earth organic elements (Eu(TTA)3, Eu(TTA)3·Phen,
Eu(TTA)3·(TPPO)2, Tb(AA)3·(TPPО)2, and Yb(TTA)3·(ТPPО)2, where ТТА is used for
tenoyltrifluoroacetone, Phen for phenanthroline, TPPO for triphenylphosphineoxide, and АА for
acetylacetone), diphenylbenzoxazolyl biphenyl (DBB-4,4′-bis[-1-(1,3-benzoxazole-2-yl-2ethynyl)] biphenyl and its substitutes) and coordinated Zn compound with an organic ligand. All
substances were synthesized using original techniques. The spectral and luminescent properties
of the compounds were investigated in solutions and films prepared by centrifugation with the
help of an Evolution-600 spectrophotometer, an SM 2203 spectrophotometer-spectrofluorimeter,
and a Cary Eclipse spectrofluorimeter. The film morphology was investigated using a Nicolet
Centauris 600 IR microscope and a Solver HV atomic power microscope. The
ITO/PEDOT/PVC:X/CaMg/Ag electroluminescent structures were synthesized, where X is used
for the above-enumerated examined compounds. Polyvinylcarbazole (PVC) was used to prepare
films by centrifugation. Organic layers and cathodes were deposited using VUP-5 and AUTO306 facilities. The film thickness was controlled by the known methods. The
electroluminescence spectra were registered with an Avantes fiber spectrometer, and the currentvoltage and brightness-voltage characteristics were registered using a specially designed stand.
Laws of changing the spectral and luminescent properties of the examined compounds in films
were established depending on the compound structure. The electroluminescence spectra are
investigated, and the nature of the observed emission bands is discussed. The emission spectra of
the examined molecules cover a wide wavelength range from dark blue (diphenylbenzoxazolyl
biphenyl) to near-IR (Yb (TTA)3·(TPPO)2).
23
LEPR STUDY OF CHARGE TRANSFER PHOTOINDUCED
IN POLYMER/FULLERENE BULK HETEROJUNCTIONS
V.I. Krinichnyi, E.I. Yudanova, N.N. Denisov
Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
kivi@cat.icp.ac.ru
Electronic processes carrying out in bulk heterojunctions formed by poly(3-alkylthiophene)
(P3AT) and fullerene derivative, [1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61] (PCBM),
attracts growing interest during last years due to perspective applications of the P3AT/PCBM
composite in molecular electronics and photonic. The irradiation of such a system by visible
light excites electron transfer from polymer chain to the fullerene molecule accompanied by the
formation of the paramagnetic polaron P+• and fullerene anion-radical C61–•. The power
conversion efficiency of such solar cells should obviously depend on dynamics properties of
these paramagnetic centers. In the present report are discussed the first results of the lightinduced EPR (LEPR) study of P3AT/PCBM composites with hexyl (P3HT) and dodecyl
(P3DDT) alkyl substitutes irradiated by laser beam with photon energy of 1.8 – 3.4 eV at 77 –
200 K.
LEPR spectra of radical pairs photoinduced in the P3AT/PCBM system directly in the
spectrometer cavity was shown to consist of two lines at g1 = 2.0023 and g2 = 2.0001 attributed
to the polaron P+• and fullerene anion-radical C61–•, respectively. These radicals recombine at T >
180 K and the rate of such a process is governed by the laser photon energy. A decay of longliving radical pairs photoinduced in P3AT/PCBM composites was interpreted to depend
strongly on a spatial distance between photoinduced charge carriers. The long lifetimes are
solely ascribed to the long spatial distances that build up among the remaining photoinduced
charge carriers, which did not recombine at a shorter time.
At the increase of microwave field in a spectrometer cavity these spectra are broadened, so then
both the spin-lattice and spin-spin relaxation times were determined by the steady-state
saturation method. The polaron diffusion along and between polymer chains as well as the
rotational diffusion of fullerene ion-radicals induce an additional magnetic fields in the
whereabouts of electron and nuclear spins which, in turn, accelerates electron relaxation in both
spin ensembles. This allowed to determine separately all these dynamics parameters. The
dynamics of both the photoinduced charge carriers was interpreted in terms of their activation
hopping over energy barriers Eb.
The analysis showed that at the increase of photon energy from 1.88 eV up to 2.22 eV and then
up to 2.75 eV the value of Eb of polarons photoinduced in P3DDT/PCBM composite first
decreases from 65 meV down to 44 meV and then increases up to 95 meV. In the same time this
value of fullerene molecules decreases monotonically from 24 meV down to 9 meV and then
down to 6 meV. These energetic parameters obtained for P3HT/PCBM composite are
characterized by extremal dependence on the photon energy near 2.0 and 3.1 eV. This can be a
result of the formation of charge carriers in heterogeneous domains of this composite.
Inhomogeneous ordering of such domains originates a variety of their band gap and, hence,
sensitivity to photons with defined but different energy. The temperature annealing of
P3HT/PCBM enhances its dimensionality (crystallinity) due to the formation of polymer
crystallites and fullerene clusters that improves main electronic properties of plastic solar cells.
The strategy of a creation of plastic solar-cells with optimal energetic is discussed.
This work was partly supported by the Russian Foundation for Basic Research (Grant No 08-0300133) and the Human Capital Foundation (Grant No 27-02-5).
24
OPTICAL AND ELECTROPHYSICAL PROPERTIES
AND APPLICATIONS OF ORGANIC AND ORGANIC-INORGANIC
THIN FILM NANOSTRUCTURES
A.V. Kukhta
B.I. Stepanov Institute of Physics NAS, Minsk, Belarus
kukhta@imaph.bas-net.by
Thin film nanostructures based on π-conjugated organic compounds and their combination with
inorganic nanoparticles attract wide attention of researchers owing to both the unique properties
and the possibility of manifold practical applications. In such nanostructures the optical and
electrophysical properties depend essentially on molecular structure and solid state organization.
In this talk a short review on the studies of some optical and electrophysical properties and
applications of organic and organic-inorganic thin film nanostructures made in the B.I. Stepanov
Institute of Physics of the National Academy of Sciences of Belarus jointly with other
researchers are presented.
The effect of the substrate nature, the molecule structure, and the deposition rate on optical and
luminescent properties, morphology and photostability, is shown using dibenzoxazolylbiphenyl
derivatives as typical example. It was revealed the reversible molecular reorganization resulting
to the formation of partially ordered structures with luminescence polarization and radiating
ability depending on the film temperature below the glass transition. The presence of oxygen was
found to cause the essential luminescence quenching. The effect of adsorbed oxygen on
electrophysical properties of some organic thin film nanostructures was also found.
New electroluminescent materials based on dibenzoxazolylbiphenyl derivatives as well as doped
and grafted polymers, conducting and cathodoluminescent nanocomposites, nitrogen dioxide
sensor, etc. are proposed.
The different kind additives are widely used to change polymer properties. The examples of
additives are conductor (metal) or semiconductor (organic and inorganic) nanoparticles with a
shell from organic material. We found that insertion of aromatic thiol into the shell of silver and
gold nanoparticles in thin films based on polyepoxypropylcarbazole matrix results in the
conductivity increase several orders of magnitude depending on temperature. IR spectroscopy
data are the evidence of the formation of bond between SH functional group and nanoparticle
surface. The strong conductivity dependence on oxygen concentration has been observed for
polythiophene-Au nanoparticles nanocomposite. Cathodoluminescence of the composite based
on polyfluorene and CdS nanoparticles was observed.
New electroluminescent materials based on dibenzoxazolylbiphenyl derivatives as well as doped
and grafted polymers, conducting and cathodoluminescent nanocomposites, nitrogen dioxide
sensor, etc. are proposed.
25
EFFECT OF J-AGGREGATES ON OPTOELECTRONIC PROPERTIES
OF CONDUCTING POLYMERS
E.I. Maltsev, D.A. Lypenko, O.M. Perelygina, S.I. Pozin, A.V. Vannikov
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
eugenemalt@rambler.ru
We have revealed that one of the types of molecular organic crystals, known as J-aggregates, are
able to modify dramatically optoelectronic properties of electroactive polymers. Polyaniline
(PANI) was used as an efficient hole-conducting matrix belonging to the most important and
widely used conducting polymer materials. PANI is particularly perspective, as functional
material, in polymer optoelectronics, for example, in manufacturing multilayer organic lightemitting diodes (OLEDs). So far PANI was successively used in OLEDs as efficient p-type
injection layer.
Here we report on the electroluminescent properties of the composites based on a new
conducting form of PANI, a water-soluble interpolymer complex obtained by a matrix method
for the first time. As a nanophase-dopant we took J-aggregates of cyanine dyes. These nanosized
particles are effective electroluminescent centers in polymer composites, thanks to their ability of
accepting energy of the excited states. PANI water-solubility allowed using it as electroactive
polymer matrix compatible with the J-aggregates nanophase. Being ionic salts, cyanine dye
molecules easily giving molecular crystals (J-aggregates) in aqueous solutions. Because these
nanosized particles have numerous geometrical forms (one-, two, and three-dimentional
structures) and strongly affect optoelectronic properties, the study of the J-aggregates-based
composites in water-soluble conducting matrices is of particular importance. It follows from our
data that that electroluminescent behavior of the PANI/J-aggregates composites in the lightemitting layers of polymer light-emitting diodes (PLEDs) differs completely from that of all
other systems. In particular, no electroluminescence was observed in PANI layers in the absence
of nanoparticles. With a gradual increase in J-aggregate concentration in the PANI layers, a
shortwave electroluminescence band appears, with a maximum at 400 nm. Its shape is identical
with that of the PANI photoluminescence. The occurrence of the PANI intrinsic
electroluminescence in the presence of J-aggregates is explained by combining different special
features of the components constituting the nanocomposite and determining entirely the system’s
unusual optoelectronic behavior. Among these special features, we first of all mention the PANI
redox-heterogeneity, that is, the simultaneous presence in the polymer bulk of p-type conducting
areas and photoluminescent light-emitting nonconducting ones. The study of PANI layers by the
Kelvin-microscopy confirmed the redox-heterogeneity of the polymer. On the other hand, Jaggregates play a crucial role in the composite. These particles demonstrate effective electronhole transport; they may have different geometrical form depending on the structure of cyanine
dye molecules. According to AFM-data, J-aggregates used in this study form very thin (0,95 –
1,1 nm), wide ribbons.
Thus, light-emitting polymer composites based on the J-aggregate-nanocristal-doped PANI are
prepared and studied. Intrinsic electroluminescence of the PANI is recorded for the first time. It
emits in the blue region. The observed emission is due to the polymer red0x-heterogeneity, as
well as the structural and electron-hole-transport properties of the J-aggregate nanocrystals.
This work was supported by the International Scientific and Technical center (project no. 3718).
26
FABRICATION OF NANO SPACE
FOR CONTROL OF INCIDENT LIGHT FIELD
H. Masuda1, T. Kondo2
1 - Tokyo Metropolitan Univ./KAST, Tokyo, Japan
2 - KAST, Kanagawa, Japan
masuda-hideki@c.metro-u.ac.jp
The fabrication of functional optical devices based on the ordered structures from submicron to
nanometer scales has attracted increasing attention due to its applicability for various fields. We
describe here the results of the preparation of highly ordered anodic porous alumina and its
application to the fabrication of various nano-spaces, which can control the electric fields of
incident light. Anodic porous alumina, which is formed by anodization of Al in acidic solution,
is typical self-ordered material [1,2]. Anodic porous alumina with highly ordered nanohole
arrays can be used for the preparation of several types of functional optical devices. Ordered
hole array structures are promising for the preparation of two-dimensional (2D) photonic
crystals, due to the highly ordered periodic structure [3,4]. Anodic porous alumina with hole
array of submicron lattice constant exhibited a 2D photonic band gap in the visible wavelength
region. The observed gap in the transmission spectra of the anodic porous alumina showed good
accordance with the calculated value.
Anodic porous alumina with highly ordered hole array structures can also be used for the various
kinds of plasmonic devices [5,6]. The ordered metal structures prepared from highly ordered
anodic porous alumina show unique optical properties originated from the localized surface
plasmon, which was dependent on the size and shapes of the structures.
[1] H. Masuda and M. Satoh, Jpn. J. Appl. Phys., 35, L126 (1996).
[2] H. Masuda and K. Fukuda, Science, 268, 1466 (1995).
[3] H. Masuda, M. Ohya, H,. Asoh, and M. Nakao, Jpn. J. Appl. Phys., 38, L1403 (1999).
[4] H. Masuda et al., Adv. Mater., 18, 213 (2006).
[5] F. Matsumoto, M. Ishikawa, K. Nishio, and H. Masuda, Chem. Lett., 34, 432 (2005).
[6] T. Kondo, K. Nishio, and H. Masuda, Appl.Phys. Express, 2, 032001 (2009).
27
LASER AND ORGANIC NANOPARTICLES
H. Masuhara
Nara Institute of Science and Technology, Japan and National Chiao Tung University, Taiwan
masuhara@masuhara.jp
Studies on organic nanoparticles have received much attention, and new preparation, novel
phenomenon, interesting dynamics, and important optical property of molecular nanocrystals and
polymer nanospheres are being examined extensively by utilizing lasers and microscopes. Indeed
a new stage of nanophotonics research is being opened by integrating photochemistry, optics,
and nano/bio materials studies (1, 2). Here we report some of our recent developments and
discuss the relevant progresses.
The top-down method for preparing very small organic nanocrystals is laser ablation in solution.
Their size, shape, of phase can be controlled by tuning laser wavelength, pulse width, fluence,
repetition rate, and shot number, and by changing solvent and temperature. The smallest size is
13 nm, which is obtained by fs irradiation (3).
It is important to understand optical properties of nanoparticles as functions of their size, shape,
internal structure, and environmental condition. Light scattering and fluorescence spectroscopic
system coupled with AFM was developed and applied to single nanoparticles on substrate, some
of which was already presented in the Terenin Symposium 2006 by us (4). This single
nanoparticle spectroscopy is now extended to single nanoparticles in solution by combining
microspectroscopy with laser trapping technique (5).
Assembling of nanoparticles in solution was achieved by laser trapping with a focused intense
near infrared CW laser beam. The assembling dynamics was probed by fluorescence and
fluorescence correlation spectroscopies (6) and prepared materials were analyzed..
When the laser trapping is accompanied with the deformation of solution surface and convection
in solution, molecular crystallization is induced, which was first demonstrated for glycine in
heavy water (7). We are now exploring new molecular systems showing “Laser Trapping
Crystallization” and studying their dynamics and mechanism by time-resolved spectroscopy and
imaging.
<References>
(1) H. Masuhara, H. Nakanishi, K. Sasaki Ed. “Single Organic Nanoparticles”, 2003, Springer.
(2) H. Masuhara, S. Kawata Ed., “Nanophonics: Integrating Photochemistry, Optics, and
Nano/Bio Materials Studies”, 2004, Elsevier.
(3) T. Asahi, T. Sugiyama, H. Masuhara, Accounts Chem. Res., 2008, 41, 1790H.
(4) Masuhara, T. Asahi, “Spectroscopy and photochemistry of single organic nanoparticles”,
Abstracts of the A. N. Terenin Symposium 2006.
(5) Y. Tanaka, H. Yoshikawa, H. Masuhara, J. Phys. Chem. B., 2006, 110, 17906.
(6) C. Hosokawa, H. Yoshikawa, H. Masuhara, Phys. Rev. E, 2005, 72, 021408.
(7) T. Sugiyama, T. Adachi, H. Masuhara, Chem Lett., 2007, 36, 1480-1481; 2009, 38, 432
28
QUANTITATIVE ANALYSIS OF PH AND METAL IONS SENSITIVE
PHOTOCHROMIC SPIROPYRANS AND SPIROOXAZINES
J.C. Micheau
CNRS, University Toulouse III, France
micheau@chimie.ups-tlse.fr
There is considerable interest in photochromic molecules such as spiropyrans, spirooxazines,
azobenzenes, fulgides and diarylethenes. They undergo photochemically triggered changes in
optical absorption, charge or ion chelation ability. Hence, they could find potential applications
in various areas, from Life sciences to Environmental sciences and information processing
technologies.
When bearing appropriate chelating functional groups or heterocycles, spiropyrans are able to
bind and release metal-ions in response to light stimuli. Their metal ion affinity can be
modulated according to their closed spiro or open merocyanine states.
There is thermochromic equilibrium between the two states. However, in presence of metal-ions
such as Co(II), Ni(II), Cu(II), Zn(II), Cd(II), etc., asymmetrical Job diagrams confirmed the
presence of several coupled equilibria related to the formation of various spiropyran/metal
complexes. Combination of independent low temperature NMR measurements of the
thermochromic equilibria and numerical modelling of the absorbance vs time curves recorded
during metal-ion complexation allowed us to determine the various spectral, kinetic and
thermodynamic parameters of the metal chelation.
Photochromic spirooxazines often exhibit similar properties. If their solutions are acidified, they
slowly turn intensely red. This spectral change has been attributed to the formation of the monoprotonated merocyanine. By turning the UV light on and off and adjusting the pH, such systems
are able to switch between three forms (closed, open and open protonated) modulating their
response as a function of several external inputs, thus mimicking logic gates behaviour.
Their ability of metal-ion or proton scavenging under UV irradiation followed by their release
under visible light makes the photochromic spiro-compounds very versatile to find applications.
For instance, in analytical chemistry, on-line micro-fluidic devices based on spiropyran or
spirooxazine photochromism and ionochromism could be realised to demonstrate the
photonically controlled accumulation and release of ions.
29
CALIXARENE-BASED COMPLEXES AS PROMISING LUMINOPHORES
FOR LUMINESCENT SILICA NANOPARTICLES
A.R. Mustafina, S.V. Fedorenko, O.D. Konovalova, A.I. Konovalov
A.E. Arbuzov Institute of Organic and Physical Chemistry, Kazan SC RAS, Kazan, Russia
asiyamust@mail.ru
Luminescent nanoparticles are of particular interest nowadays due to their wide application in
biochemichal analysis, medicine and nanophotonics.
Two main ways of getting luminescent nanoparticles are commonly
used. The first way is to fix luminophores on a nanoparticles
surface through covalent bonding, the second way is a doping
luminophores within a nanopartcles core. The second way is more
preferable, since it does not prevent further modification of a
nanoparticles surface by anchoring groups, which is of particular
importance in the development of biomarkers. We have chosen the
second way to obtain the silica coated Tb(III) nanoparticles,
exhibiting high and stable in time luminescent properties. The high
luminescence of Tb(III) doped nanoparticles is the result of Tb(III) coordination with psulfonatothiacalix[4]arene (TCAS), which is acting as the efficient antennae for Tb(III)-centered
emission. The quenching through the ion exchange of Tb(III) by H+ or La(III) is time-dependent,
indicating that the ion exchange is probably diffusion controlled. The quenching by Co(III)
complex cations is achieved by energy transfer mechanism and thus is not time-dependent. The
analysis of quenching data in Stern-Volmer cooordinates reveal the negative charge of silica
coated Tb(III)-TCAS nanoparticles and several types of luminophoric species, located within the
core and close to the surface of silica nanoprticles. The advantages and perspectives of the use of
lanthanide complexes with various sulfonated calix[4]arene derivatives as luminophores for the
synthesis of luminescent silica nanoparticles are discussed.
We thank RFBR (grant N 07-03-00282) and BRHE REC 007 for financial support.
1. Skripacheva, V. V.; Mustafina, A. R.; Rusakova, N. V.; Yanilkin, V.V.; Nastapova, N.V.;
Amirov, R. R.; Burilov, V.A.; Zairov, et al, Eur.J. Inorg.Chem. 2008, 3957–3963.
2. A.R. Mustafina, S.V. Fedorenko, O.D. Konovalova, A. Yu. Menshikova, N.N. Shevchenko,
S.E. Soloveva, A.I. Konovalov, I.S. Antipin, Langmuir, 25, 2009, 3146-3151.
30
LOW-THRESHOLD TRANSFORMATION OF FREQUENCY
IN SOLID SOLUTIONS OF Zn0.6Cd0.4S
WITH ADSORBED METAL-ORGANIC CLUSTERS
O.V. Ovchinnikov, M.S. Smirnov, L.Yu. Leonova,
E.A. Kosyakova, A.N. Latyshev, V.G. Kluyev
Department of Optics and Spectroscopy, Voronezh State University, Russia
opt@phys.vsu.ru
Working out the materials for the control and management of different parameters of the light
stream with the help of the optical transitions and switches is a fundamental and important
problem. Therefore, the materials in which anti-Stocks luminescence (ASL) is possible are really
essential for solving such kind of problems. Semiconductor crystals with volume and surface
metal and organic impurity centers, semiconductor heterostructures, systems with quantum dots
and quantum gaps are considered to have the greatest potential. However, the thresholds of antiStocks transformations were high 1-103 W/cm2 in a lot of mentioned materials. In other cases the
thresholds were not high 10-1-10-3 W/cm2 and the effect occurred at low temperatures (77–4.2 К)
Possibility of low-threshold (10-2-10-4 W/cm2) anti-Stocks transformations of radiation with the
wavelength 620 - 720 nm into the luminescence in the area 520 - 580 nm in small disperse
crystals (SDC)of highly cleanliness solid solutions of Zn0.6Cd0.4S with adsorbed molecules of
dyes and silver subnanoclusters at temperatures 77 - 300 K is described in this work. The
spectral interval for the wavelength of radiation, which can be transformed into
photoluminescence of Zn0.6Cd0.4S crystals, was determined from the ASL excitation spectrum.
Comparing of these spectra with the spectra of the absorption of adsorbed molecules of dyes
made it possible to determine the role of the dye molecules in the process of ASL excitation. The
changes in the distribution of density of impurity surface states of SDС Zn0.6Cd0.4S as the result
of the dye molecules and silver subnanoclusters adsorption on the surface of the crystals were
under control. The method of infrared (IR) stimulated flash luminescence (SFL) was used for it.
The spectrums of ASL excitation of these samples were completely positional identical to the
spectrums of luminescence that was obtained with the UV excitation of the crystal in the area of
the fundamental band of the adsorption. This fact proves that there is the same nature of the
centers of radiated recombination of ASL and usual proper recombination luminescence of SDС
Zn0.6Cd0.4S. The next important result of the work is the discovery of the effect of intensity
change of ASL and, therefore, effectiveness of its excitation as a result of the influence of midget
concentration of silver-containing solutions (10-6 – 10-8 mole AgNO3/moleZn0.6Cd0.4).
It has been shown that the two-quantum inter-band optical transitions are realized sequentially
with the transference of the energy of the electronic excitation from the dye molecule to the
adsorbed on the surface Zn0.6Cd0.4S silver subnanoclusters forming deep local conditions with
the photoionization energies of 1.80-2.00 eV in the forbidden gap. The evaluation of quantum
effectiveness of the process of ASL was carried out taking into consideration the losses of
luminescence while it was detected. Still it was 10-4 -10-5 for the streams 10-2 W/cm2 at room
temperature.
The authors acknowledge the funding support from the Russian Federal Property Foundation
(through Grant No. 08-02-00744).
31
SUPRAMOLECULAR WATER-SOLUBLE
COMPLEXES OF CAROTENOIDS
N.E. Polyakov1, T.V. Leshina1, E.S. Meteleva2,
A.V. Dushkin2, T.A. Konovalova3, L.D. Kispert3
1 - Institute of Chemical Kinetics and Combustion SB RAS, Novosibirsk, Russia
2 - Institute of Solid State Chemistry and Mechanochemistry SB RAS, Novosibirsk, Russia
3 - Department of Chemistry, University of Alabama, Tuscaloosa, AL, USA
polyakov@kinetics.nsc.ru
Carotenoids are a class of pigments wide spread in nature, which also serve as an antenna,
photoprotective device and intermediate electron carrier in photosynthetic reaction center.
Carotenoid radicals play a crucial role in electron transfer and proton transfer processes in
photosynthesis and in the design of improved artificial solar cells, as well as in the scavenging of
toxic free radicals. At the same time, wide practical application of carotenoids is substantially
hampered by their hydrophobic properties, instability in the presence of oxygen and metal ions,
and high photosensitivity. Application of the “host-guest” inclusion complexes was first related
to an attempt to minimize the aforementioned disadvantages of carotenoids when these
compounds are used in food processing (colors and antioxidant capacity) as well as for
production of therapeutic formulations considering the better solubility and consequently higher
bioavailability.
In the present work, we report the first example of water soluble carotenoid complexes with
natural polysaccharide arabinogalactan (AG). It was demonstrated that incorporation of
carotenoids into arabinogalactan macromolecule results in significant change in their properties.
The increase of water solubility (up to 5 mM), photostability (a factor of 10 increase) and
stability by a factor of 20 towards metal ions in solution has significant importance in the
practical application of carotenoids [1]. In addition the protection of carotenoids from the
reactive oxygen species by arabinogalactan was demonstrated. On the other hand, inclusion
complexes of some carotenoids with natural triterpene glycoside, glycyrrhizic acid (GA), show
enhanced ability (in orders of magnitude) to scavenge free radicals [2]. A very important
observation is determining the effect of GA on the oxidation potential of carotenoids.
The most interesting results were obtained on the study of photoinduced electron transfer
between carotenoid complexes and TiO2 nanoparticles in solid state and in solution. An
important result of these studies is the considerable increase in the yield and stability of the
radical cation of carotenoid in solid state AG complex, and significant increase in the yield of
free radicals in solution. High stability of the carotenoid radical cation imbedded into nanosized
polysaccharide host opens wide possibilities of the application of these complexes for design of
artificial light-harvesting, photoredox and photocatalytic devices.
The financial support of Russian Foundation for Basic Research, grant 08-03-00372 and the
U.S. Department of Energy, Grant DE-FG02-86ER13465 are also gratefully acknowledged.
References:
N.E. Polyakov, e.a. Water Soluble Complexes of Carotenoids with Arabinogalactan. J. Phys.
Chem. B 2009, 113, 275-282.
N.E. Polyakov, e.a. Antioxidant and Redox Properties of Supramolecular Complexes of
Carotenoids with β-Glycyrrhizic Acid. Free Rad. Biol. Med. 2006, 40, 1804–1809.
32
BRANCHED AND DENDRITIC POLYARYLSILANES
AS NANOSTRUCTURED LUMINOPHORES
S.A. Ponomarenko, N.M. Surin, O.V. Borshchev,
Y.N. Luponosov, E.A. Shumilkina, A.M. Muzafarov
ISPM RAS, Moscow, Russia
ponomarenko@ispm.ru
One of the prospective methods of organic nanostructured materials creation for photonic and
optoelectronic devices is chemical coupling of chromophores into macromolecules having
branched and dendritic structure. Luminescent dendrimers, having dimensions in the range of
several units to several decades of nanometer, show unique optical properties: huge molar
extinction coefficient, “molecular antenna” effect, record high photo- and electroluminescent
efficiency [1].
In this work a new approach to formation of polyarylsilanes of branched and dendritic structure,
consisting from oligoarylene fragments of different conjugation length, linked to each other
through silicon atoms being also the branching points. Preparation of these compounds is based
on the combination of organometallic reactions leading to aryl-aryl coupling (Suzuki, Kumada)
with organosilicone chemistry (reaction of chloro- and alkoxysilanes with organolithium and
organomagnesium thiophene derivatives). Investigation of the optical properties of the
compounds obtained revealed that silicone atoms brakes the conjugation between the adjacent
oligoarylene fragments, but their presence in the dendritic structure can increase the
CH
luminescence efficiency in 10-15 times [2]. For the
CH
S
first time among organosilicone compounds the
S
effect of “molecular antennae” was shown for the
S
S
CH
Si
dendrimers
consisting
of
different
Si CH
S
S
S
S
S
S
oligothiophenesilane fragments within the same
H C
S
S
S
CH
S
macromolecule [3]. This effect means that the whole
Si
HC
macromolecule absorbs photons in the wide spectral
S
region, then efficient intramolecular energy transfer
S
takes place, and only the fragments with the largest
S
conjugation length, located in the center of the
CH
Si
S
S
molecule, emits the light (Fig.1). Peculiarities of the
S
H C
S
CH
optical properties of such compounds will be
considered in the presentation. Preliminary results
Fig.1. Structural formula of the first
have shown good properties of functional layers
organosilicone dendrimer –
made from polyarylsilanes of branched and dendritic
“molecular antennae”
structure in different devices: organic light emitting
diodes, photovoltaic cells, plastic scintillators.
6
13
6
13
3
3
13
6
6
13
3
3
13
6
6
13
Authors thanks for financial support Russian Foundation for Basic Research (grant 07-0301037), Russian Federal Agency for Science and Innovations (contract No. 02.513.11.3382) and
Russian Academy of Sciences (Program Presidium №27).
[1] S.A. Ponomarenko, O.V. Borshchev, Y.N. Luponosov, A.M. Muzafarov, Luminescent
dendrimers, All Materials, Encyclopedic Hand-book, 2008, №2, с.13-22; №3, с.36-45.
[2] Y.N. Luponosov, S.A. Ponomarenko, N.M. Surin, A.M. Muzafarov, Organic Letters 2008,
10, 2753-2756.
[3] Y.N. Luponosov, S.A. Ponomarenko, N.M. Surin, O.V. Borshchev, E.A. Shumilkina, A.M.
Muzafarov, Chemistry of Materials 2009, 21, 447-455.
33
THE EFFECT OF METALIC NANOPARTICLES ON THE OPTICAL
CHARACTERISICS OF PORPHYNATES AND MEH-PPV SOLUTIONS
A.A. Revina1, M.G. Tedoradze1, Yu.A. Plachev1, I.V. Bogdanova2
1 - A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
2 - D.I. Mendeleev University of Chemical Technology of Russia, Moscow, Russia
revina@mail333.com
Spectrophotometric investigation of the metallic nanoparticles interactions with different
porphyrinates and with light-sensitive polymer, poly- 2-metoxy-5-(2-ethylgexyloxy)-1,4phenyllenvinylene, MEH-PPV in the organic solutions were performed in order to learn the
influence of different additives on the solar energy absorption and the energy transformation by
photoactive polymer layers. Prior to it, optical absorption and luminescence spectra of Ag, Pd,
Pt nanoparticles, and spectra of the MEH-PPV and porphyrinates Pd(II) and Pt(II) in the
solutions were determined.
Stable metal nanoparticles in liquid phase were produced in reverse Н2О/АОТ/аlcane micelles
as microreactrs using radiation-chemical method at “Lanacom Ltd.” laboratory [1]. The
porphyrinates were synthesized at IPCE New Physicochemical Problems Laboratory [2]. UVVIS Specord (Shimadzu) was used for optical absorption spectra measurements. Fluorescence
spectra registration was performed with Hitachi F-7000 spectrometer.
To determine reciprocal influence of Pt, Pd nanoparticles and selected porphyrinates, various
volumes of reverse micellar solutions with ω=[Н2О]/[AOT]) containing metal nanoparticles,
with initial metal ion concentration of ~ 4.0х10-4 М were added to optically sensitive light
porphyrinates. In case of Ag nanopartiles, the study was done using solutions with metal
concentration increased by order of magnitude, while ω values varied from 1.5 to 8.0.
There is a known dependency between fluorescence emission quenching capabilities and
photovoltaic parameters of energy converters. Our study has proved that admixture of Pt(II)
ions to the porphyrines (H2TCP) does not make impact on its luminesce characteristics, while
addition of Pt nanoparticles (NP) to porphyrine PdТСР solution causes quenching of
luminescence in the range of ~ 660 nm. Along with porphyrine’s luminescence quenching the
buildup of Pt NP’s luminescence was observed (λмах~ 510-540 nm).
Similar effect was determined during examination of Pt NP and Pt porphynates (PtTCP)
interaction. In case of Pd NP related study, the intensity of the main porphyrinte luminescence
band (λmax1=660nm) increased by 15%. Addition of Ag NP to PdТСР has shown only decrease
of luminescence band (λmax1=660 nm). Or study of reciprocal influence of PtТСР and Ag NP
reveled NP size effect on decrease of fluorescence intensiy.
Voltaic data measured for
photosensitive МЕН-РРV layers prove that the addition of Ag NP, synthesized I reverse micelles
with ω0=5, most efficiently increase the photovoltaic parameters of the layers, and causes
luminescence quenching.
1. Patent RF № 2147487, priority date as of 20.04.2000.
2. A.Yu. Chernyad’ev, N.M. Logacheva, A.Yu. Tsivadze// Journal of Inorganic Chemistry.
2005. Vol. 50. № 4. P.615.
The research is supported by grants of RFBR № 08-03-00796 and № 09-08-00758.
34
SPECTRAL AND LUMINESCENT PROPERTIES OF SEVEREL
ACRIDINE COMPOUNDS IN SOLUTIONS AND SiO2-FILMS
L.G. Samsonova, N.I. Selivanov, T.N. Kopylova, V.Ya. Artyukhov, T.A. Solodova
Tomsk State University, Russia
slg@phys.tsu.ru
Optical chemical sensors that use luminescence, including changes of the radiation intensity,
radiation wavelengths, spectral shape, and luminescence life-time possess high sensitivity and
selectivity toward molecules of different analytes. The targeted search of compounds exhibiting
sensor properties and the design of optical sensor materials on their basis is a topical task.
The acridine dyes are suitable compounds for creation of a material for an optical sensor.
The spectral, luminescent properties, dipole moment in base and in excited states, photophysical
processes of deactivation of excitation energy for acridine, 9-aminoacridine and 2,7-dimethyl-9ditolylaminoacridine (9-DTAA) and for their protonated forms were investigated experimentally
and using quantum mechanical simulation.
It was shown that in this molecules the nitrogen of acridine cycle is a protonation site. The more
strong changes of spectral properties under protonation were observed for acridine: the
fluorescence maximum considerably shifted in the red region and a fluorescence quantum yield
increased up to 0,27 (for neutral form it is equal 0,03).
For a 9-DTAA protonated form the fluorescence is absence. In results of carried out quantumchemical calculations it was shown that for investigated molecules the lowest singlet and triplet
states have ππ* orbital nature and very week fluorescence for acridine and protonated 9-DTAA
is result of strong singlet – triplet conversion. For acridine protonated form the rate constant of
singlet – triplet conversion decreases on several degrees.
So considerable change of spectral-luminescent properties enables to use acridine protonated
form as the active medium for detection of small amount of substances with the basic properties,
for example ammonia.
Suitable material for a matrix of an optical sensor is the material made from tetraethoxysilane
(TEOS) received sol-gel method and doped with organic compound (acridine). Since in synthesis
acid hydrolysis was used acridin was in protonated form.in the final product
The sensor material was made in form of thin (< 1 µm) films by spin-coating method.
To study the capability of the received material to be a sensor for ammonia the investigation of
fluorescence spectra behavior of samples doped the acridine at contact with ammonia vapor was
carried out. In result of interaction ammonia vapor with film surface the fluorescence intensity of
protonated acridine fall down. It was caused by greater basicity of ammonia in comparison with
a molecule acridine, that leads to transition of a proton from acridine nitrogen to a molecule of
ammonia at their contact. The dependence of ammonia vapors concentration on fluorescence
intensity was investigated.
Thus, the possibility of creation of optical sensors on the basis of organic compounds
incorporated in thin silicate films was shown.
35
OPTOELECTRONIC SENSOR SYSTEMS
BASED ON THIN FILM ORGANIC ELECTRONICS
H.F.M. Schoo1, M.M. Koetse1, P.A. Rensing1, G.T. Van Heck1,
N.N.M.M. Meulendijks1, M. De Kok1, P.G.M. Kruijt1, F.P. Wieringa2
1 - Holst Centre
2 - TNO
herman.schoo@tno.nl
In many practical applications, the ideal sensor device would be thin, lightweight and flexible.
These are properties, generally attributed to Thin Film Organic Electronic Devices, which makes
them a good candidate for future sensor applications. (Combinations of) devices like organic
light emitting diodes (OLED), Organic Field Effect Transistors (OFETs) and organic
photodiodes (OPD) may be used to create innovative sensors. Furthermore, they would
preferably be cheap, so that (high end) disposable sensors would become an option. Therefore
we set out to develop an optical sensor platform having OLED, OPD and organic circuitry
modules as core elements. The fabrication technology for these modules is developed to be
compatible with mass production, and will be based on printing and reel-to-reel processing.
Here, we show that OLEDs and OPDs can be used in a wide range of optical sensors. Printing
technologies allow for cheap production of devices. Using a modular build up of these and
additional components such as organic circuitry and/or embedded thinned silicon dies will allow
for an almost two-dimensional design with a variety of resulting products. As an example the
design and the fabrication of modules for a pulse-oximeter device and integration into a wireless
smart bandage will be discussed.
36
FULLERENE NANOCLUSTERS AS AMPLIFIERS
IN LINEAR SPECTROSCOPY AND NON-LINEAR OPTICS
E.F. Sheka
Peoples’ Friendship University of Russia, Moscow, Russia
sheka@icp.ac.ru
The enhancement of linear and non-linear optical properties results from two filed effects
referred to as field confinement and field resonance. Thus, arranging the space around or nearby
a polarizable object in a manner of either open (caves and planar structures) or closed (droplets)
nanocavities influences a particular spatial distribution of the
field around the object that causes an enhancement of the light
emitted by the object. On the other hand, a strong increase of
spontaneous and stimulated emission of the object additionally
occurs when either incoming or outgoing field is resonant with
local excitations of the cavity atomic structure. While the first
field effect has been studied for various kinds of materials, the
resonance effect is mainly limited to nanoparticle-structured
metals, such as silver and gold, so that the resonance with
local plasmons has been considered. However, not only
plasmons but Wannier-Mott excitons as well as charge transfer
excitons may provide a considerable polarization of the
medium under excitation and thus may cause a considerable enhancement of optical properties of
an object placed inside or near a nanocavity made of the corresponding materials. Nevertheless,
studies of this kind are rather scarce and are related to semiconductive species characterized by
Wannier-Mott excitons. The paper presents first results related to the field resonance effects
caused by charge transfer excitons. This concerns the study of fullerene nanoclusters that present
nano-sized charge transfer complexes immersed in a molecular solvent. Excited by different
laser wave lengths λex , the clusters manifest clearly seen enhancement of Raman scattering and
one-photon luminescence when either λex or λem is resonant with local charge transfer excitons.
The light emission λem concerns both cluster themselves as well as surrounding solvent
molecules which makes the spectral evidence of the enhanced effects quite variable and
dependent on the chemical structure of fullerene molecules [1-3]. The experimental findings are
in good accordance with the electromagnetic theory of enhancement [4] which allows for linking
directly linear and non-linear optical properties. The latter lays the foundation of practically
important criteria that allow predicting non-linear optical behavior of the medium on the basis of
its linear spectral properties.
The work is financially supported by the RFBR (grants № 07-03-00755 and 08-03-01006).
References
1. B.S.Razbirin, E.F.Sheka, A.N.Starukhin, D.K.Nelson, P.A.Troshin, R.N.Lyubovskaya,
JETP Lett. 87, 133 (2008)
2. E.F.Sheka, B.S.Razbirin, A.N.Starukhin, D.K.Nelson, M.Yu.Degunov, L.N.Lyubovskaya,
P.A.Troshin, JETP. 108, 738 (2009).
3. E.F.Sheka, B.S.Razbirin, A.N.Starukhin, D.K.Nelson, M.Yu.Degunov, P.A.Troshin,
R.N.Lyubovskaya. J.Nanophot. SPIE 3, 033501 (2009)
4. J.P.Heritage, A.M.Glass, Surface Enhanced Raman Scattering. p.391, Plenum Press: NY
and London (1982).
37
FEMTOSECOND PRIMARY CHARGE SEPARATION
IN PHOTOSYSTEM I
I.V. Shelaev1, F.E. Gostev1, M. Mamedov2, O.M. Sarkisov1, V.A. Nadtochenko1,
V.A. Suvalov3, A.Yu. Semenov2
1 - ICP RAS
2 - IPCB MSU
3 - IFPB RAS
shelaev@bk.ru
In the last years, electron transfer reactions in photosystem I (PS I) were studied very strongly
using various ultrafast techniques, including pump-probe absorption spectroscopy. However, the
primary electron transfer reactions within PS I reaction center (RC) could not be clearly
separated from excitation energy transfer since these reactions occur within the same time range.
Nevertheless, one approach was developed to separate electron transfer from energy transfer and
to reveal the pure kinetics of primary electron transfer steps and the spectra of corresponding
intermediates.
Femtosecond experiments were carried out on setup created in Laboratory of Bio- and
Nanophotonics in Institute of Chemistry Physics Russian Academy of Scientists. The energy and
electron transfer in PS I was studied by femtosecond pump-probe absorption spectroscopy. The
excitation was performed using 20-fs laser pulses centered at 720 nm. The predominantly
selective excitation of the special pair P700 chlorophyll (Chl) in the RC results in the appearance
of the spectra of the primary radical pair P700+A0-A1 (where A0 is the primary Chl electron
acceptor and A1 is the secondary phylloquinone acceptor) with main bleaching bands at 690 and
705 nm within 100 fs.
The subtraction of kinetic difference absorption spectra of the closed (state P700+A0A1) RC from
that of the open (state P700A0A1) RC reveals the pure spectrum of the P700+A0- ion-radical pair.
Experimental data were analyzed using simple kinetic scheme:
100 fs
k1
k2
(P*A0A1 <
→ P+A0-A1) →
P+A0A1- ,
An* →
and the global fit procedure based on the singular value decomposition analysis. The calculated
kinetics of transitions between intermediate states and their spectra coincided very well with the
kinetics recorded at 694 and 705 nm and the experimental spectra obtained using subtraction of
the spectra of closed from the spectra of open RCs. As a result, we found that the main events in
RCs of PS I under our experimental conditions include very fast (<100 fs) conversion of
P700*A0A1 to P700+A0-A1 state in apprximately half of RCs, the ~5-ps energy transfer from
antenna Chl* to P700A0A1 in the remaining part of RCs and ~25-ps formation of the secondary
radical pair P700+A0A1-.
38
ELECTRONIC SENSORS ON THE BASIS OF NANOSTRUCTURED
CERIUM OXIDE FILMS
A.N. Shmyryeva, A.V. Borisov, N.V. Maksimchuk
National Technical University of Ukraine «KPI», Kyiv
lejanel@ukr.net
The influence of technological parameters of nanostructured cerium oxide films preparation on
the electronic and structural properties was studied with the purpose of their application as an
active element of different microelectronic sensors: high-performance photoresistors and MOS –
photodiodes for bioluminescence registration, ion-selektive field-effect transistors (ISFET) and
MOS - varaktors indicating the pH changes as a result of biochemical processes.
X-ray photoelectron spectroscopy (XPS) analysis showed that, the ratio of Се3+ and Се4+
concentrations in the CeOx films vary depending on the technological parameters, foremost,
substrate temperature, that cause change of fundamental gap Eg. The correlation of these changes
with the optical and photo-electric characteristics was set.
On the basis of the developed highly sensitive photodetectors and living organisms (Daphnia
magna and bioluminescent bacteria) a portable electronic biolumenometric complex has been
created for determination of the overall toxicity, caused mycotoxin patulin, pesticides bifentrin
and chlorpyrophos. The minimum threshold of sensitiveness for patulin is 0,1 mg/l after 2 h. and
0.01 mg/l after 6 and 24 h. of experiment, bifentrin – 0.01 mg/l after 3 h. and 0.0001 mg/l after
24 h. of experiment.
It was shown that the application of nanocrystalline cerium oxide films as a dielectric of MOS structures promotes a sensitiveness and sensors stability due to the high density of the sensible
sites on the CeOх surface (to 1020 м-2), large value of dielectric constant (ε=26) and Eg (3.6 eV),
low values of leakage currents. The results of application of ISFETs and MOS - varaktors with
nanocrystalline CeOх film for creation of immune and enzyme biosensors were demonstrated.
Threshold of sensitiveness for enzyme sensors on the basis of cholinesterases to phosphoorganic
pesticides is 10-9 M, to the ions of heavy metals is 10-7 M. A рН-sensitiveness of the ISFET - 58
мV/рН, that close to the maximally possible sensitiveness for a structure semiconductordielectric-solution, so-called Nernst sensitiveness – 59 мВ/рН.
39
UV-LIGHT STIMULATED FORMATION
OF ORGANIC NANOPARTICLES
G.I. Skubnevskaya, S.N. Dubtsov, G.G. Dultseva
Institute of Chemical Kinetics and Combustion SB RAS, Novosibirsk, Russia
skubnev@kinetics.nsc.ru
The report deals with the investigation of the mechanisms of formation of organic aerosol under
photolysis of the compounds of different classes. The kinetics of photolysis and a complicated
sequence of elementary stages following the primary photoexcitation was investigated. The
yields of photonucleation were measured for aldehydes (formaldehyde, avetaldehyde,
benzaldehyde), amines and halogenated aromatics. Reactive intermediates - short-lived free
radicals were identified, gaseous and aerosol products were analyzed. Photonucleation was
studied with the help of the Diffusion Aerosol Spectrometer developed at ICKC SB RAS.
Investigations were carried out in a flow photochemical quartz reactor in the flow an inert carrier
gas and in the presence of additives: oxygen, ozone, water vapour. The kinetic data of the
investigated systems were compared with the results of physicochemical analyses of the initial
compounds, intermediate and final products in the gas phase and in aerosol, down to the trace
amounts. Mathematical modeling of photolysis at the level of elementary stages and numerical
modeling of photonucleation in coagulation mode with permanent photochemical source of the
nuclei of the dispersed phase, involvement of the electronic databases on chemical kinetics
allowed us for the first time to obtain the quantitative data on the yields of the initial stages of
photonucleation. The yield varies within the range ~ 10-1 to 10-6 in the investigated systems. The
contribution from the photonucleation of gaseous organics into the formation of nanoparticles in
the Earth’s atmosphere was estimated. The nonlinear dependencies of the dimensional and
concentration characteristics of the formed nanoparticles on photolysis parameters and on the
chemical composition of reaction mixtures were investigated. These data will open the way to
directed synthesis of organic nanoparticles of required size and composition for various
applications, including biotechnologies and medicine.
The investigation has been supported by SB RAS (1982-2004), Russian Foundation for Basic
Research (1994-2009) and CRDF (2002-2004).
40
MATERIAL SOLUBILITY AND MISCIBILITY EFFECTS
IN FULLERENE/POLYMER COMPOSITES USED AS
PHOTOACTIVE MATERIALS IN ORGANIC SOLAR CELLS
P.A. Troshin1, E.A. Khakina1, D.K. Susarova1, H. Hoppe2,
A.E. Goryachev1, A.S. Peregudov3, N.S. Sariciftci4, V.F. Razumov1
1 - IPCP RAS, Russia
2 - TU Ilmenau, Germany
3 - INEOS, Russia
4 - LIOS, Austria
troshin2003@inbox.ru
Organic photovoltaics have been subject for intensive research worldwide for the last decade. As
a result, the power conversion efficiencies of the fullerene-polymer solar cells were boosted in
2006-2007 to a commercially interesting level of 5-6 % starting from values of 0.04 % in 1993.
At the moment there is a race to develop novel fullerene-based and polymer-based photoactive
materials that can improve efficiency of organic solar cells. However, now there are no detailed
explanations in literature how the molecular structure and the properties of the materials
correlate with their performance in solar cells.
In this talk we will report results of our systematic investigation of numerous conjugated
polymer/fullerene derivative composites as active layer materials in organic solar cells.
Thirty novel fullerene-based electron acceptor materials were synthesized and evaluated in
organic bulk heterojunction solar cells with poly(3-hexylthiophene) P3HT as electron donor
component. We show that there is a good correlation between the solubility of the fullerene
derivatives in organic solvents used for film casting and the output parameters of organic solar
cells made using composites of these compounds with P3HT as active layer materials. In
particular, the best performances were obtained for fullerene derivatives possessing solubilities
comparable to the solubility of P3HT (ca.50-90 mg/ml) (Figure 1).
Twelve fullerene derivatives possessing different solubilities were combined with poly(3alkylthiophenes) bearing side chains of varied length: P3BT (C4), P3HT (C6), P3OT (C8),
P3DT (C10) and P3DDT (C12). Investigation of the resulting 60 fullerene/polymer composite
systems in organic solar cells revealed important material structure/solubility – solar cell
performance relationships that will be discussed in this talk.
In conclusion, the performed systematic investigation of numerous fullerene/polymer composites
revealed important rules for design of advanced material combinations for organic photovoltaics.
Figure 1.
41
PEPTIDES AGGREGATES AS SUPRAMOLECULAR NANOSYSTEMS.
STRUCTURE INVESTIGATIONS BY PULSED ELECTRON-ELECTRON
DOUBLE RESONANCE (PELDOR) SPECTROSCOPY
Yu.D. Tsvetkov, A.D. Milov, R.I. Samoilova
Institute of Chemical Kinetics and Combustion SB RAS, Novosibirsk, Russia
Tsvetkov@kinetics.nsc.ru
The PELDOR technique will be represented. It is shown that by analyzing the kinetics of
PELDOR signal decay due to magnetic dipolar interactions it is possible to fined the distance
between paramagnetic centers in a pairs, distance distribution function F(r) in the range 15–70
Å, to identify the radical assembling in groups and to estimate the number of the radicals in the
groups. The distances determination by PELDOR in different systems will be exemplify.
Data on the structure of supramolecular aggregates of spin-labeled trichogin dimmer, zervamicin
and alamethicin in apolar solutions will be presented together with its structural changes when
peptide/biolayers interaction is taking place.
This work was supported by the Russian Grant for Scientific Schools (НШ-551.2008.3), the
Russian Foundation of Basic Research (RFBR grant 06-04-48021-a), grant of Programme 7
Dep. of Chem. and Matherials RAS.
42
NON-LINEAR OPTICAL AND PHOTONIC CRYSTALLINE
CHROMOPHORE-CONTAINING POLYMERIC MATERIALS
FOR OPTOELECTRONICS AND OPTOSENSORICS
A.V. Yakimansky1, G.I. Nosova1, N.A. Solovskaya1, N.N. Smirnov1,
N.A. Nikonorova1, A.Yu. Menshikova1, N.N. Shevchenko1, T.G. Evseeva1,
S.P. Gromov2, S.K. Sazonov2, A.V. Koshkin2, V.A. Sazhnikov2, M.V. Alfimov2
1 - Institute of Macromolecular Compounds RAS, St.Petersburg, Russia
2 - Photochemistry Center RAS, Moscow, Russia
yak@hq.macro.ru
Non-linear optical (NLO) nanostructured materials are of great interest for optoelectronics
because they make it possible to change the frequency of the propagating light and to realize a
communication between electric and optical signals through their light-perturbed electronic
distribution.
In the present work, copolymethacrylates, polyimides, polyamidoimides, and
polyimidourethanes with covalently attached chromophore groups were synthesized. Second
harmonic generation (SHG) coefficients, d33, for corona-poled films of these polymers were
measured.
It was shown that for polyimidourethanes with imbedded 3,4-dicyanoazobenzene chromophore
groups the value of d33 exceeds 100 pm/V, making these materials perspective for optoelectronic
applications.
For copolymethacrylates, the processes of orientational relaxation of the chromophore groups,
determining the poling efficiency and, therefore, the level of achievable second order NLO
properties, were studied using the method of dielectric spectroscopy.
3D-ordered photonic crystalline arrays of monodisperse polymeric nanoparticles functionalized
with covalently attached or electrostatically adsorbed chromophores are perspective materials for
optoelectronics, telecommunication industry and optosensorics.
Monodisperse submicron poly(styrene-co-methacrylic acid) particles with surface carboxylic
groups were obtained by emulsion copolymerization. Photonic crystalline films of these particles
were prepared with cationic dyes (Rhodamine 6G and 1-(3-ammonium-propyl)-4-[(E)-2-(3,4dimethoxyphenyl)-1-ethenyl]pyridinium perchlorate) adsorbed onto their negatively charged
surfaces. These films displayed photonic band gaps, overlapping at definite directions of incident
light with their fluorescence band. Besides, the fluorescence intensity changed reversibly in the
vapors of polar solvents. This effect is perspective for design of matrix chips of gas sensors
ensuring simultaneous detection of several analytes.
The work is supported by the Federal Agency on Science and Innovation of the Russian
Federation (contract 02.513.12.3025) and by the Scientific Program “Basic research of
nanotechnology and nanomaterials” of the Presidium of the Russian Academy of Sciences.
43
FORMATION PRINCIPLES AND RELAXATION PROCESSES
IN NANOSCALE HETEROGENEOUS COMPLEXES:
MULTIPORPHYRIN ARRAYS AND CdSe/ZnS NANOCRYSTALS
E.I. Zenkevich1, C. Von Borczyskowski2
1 - National Technical University of Belarus, Minsk, Belarus
2 - Institute of Physics, Chemnitz University of Technology, Chemnitz, Germany
zenkev@tut.by
It is clear that well-defined geometry is one of the important factors requisite for enhanced lightharvesting efficiency and/or ultrafast vectorial electron transfer in natural and artificial systems.
With this idea in mind, we have elaborated the formation (in solutions and polymeric PMMA
films at 295 K) various types of self-assembled nanoscale multiporphyrin arrays of controllable
geometry and composition (up to 8 tetrapyrroles) using non-covalent two-fold binding
interactions of the meso-phenyl bridged ZnOEP chemical dimers or trimers, (ZnOEP)2Ph or
(ZnOEP)3Ph2, with di- and tetrapyridyl substituted tetrapyrrole extra-ligands.
The dynamics and mechanisms of relaxation processes
Energy Transfer
in multiporphyrin arrays as a function of redox and
photophysical properties of interacting subunits have
been studied in solvents of various polarity and
Electron Transfer
temperature (77-295 K), using static, time-resolved
picosecond fluorescent (experimental response ∆1/2 ≈
30 ps) and fs pump-probe (∆1/2 ≈ 120 fs) set-ups.
The strong quenching of the fluorescence for (ZnOEP)2Ph or (ZnOEP)3Ph2 is governed by
competing energy migration (EM) and photoinduced electron transfer (PET) processes to the
extra-ligand (∼0.9 ps). In arrays containing pentafluorinated extra-ligands PET takes place within
∼700 fs and remains still efficient in rigid solutions at 77-120 K. In the case of covalently linked
electron acceptors (A) of the non-porphyrin nature (quinone, pyromellitimide), the strong S1-state
decay shortening (fluorescence quenching) of the dimer is due to EM and PET processes to the
extra-ligand (∼0.9-1.7 ps), which are faster than a slower PET «dimer→A» (34-135 ps) in
toluene at 295 K. In these conditions, the extra-ligand S1-state decay (τS=940-2670 ps) is
governed by competing processes: a bridge (dimer) mediated long-range (rDA=18-24 Å)
superexchange PET to an acceptor, and photoinduced hole transfer from the excited extra-ligand
to the dimer followed by possible superexchange PET steps to low-lying CT states.
Inspired by work on self-assembled multiporphyrin arrays we have
succeeded in the direct labelling of TOPO capped semiconductor
nanocrystals (NC) CdSe/ZnS with tetra-pyridyl substituted porphyrins,
(H2Pm-Pyr)4, based on the coordination of the pyridyl N lone pair with QD
surface Zn or Cd atoms. Although part of the porphyrin-induced QD
photoluminescence (PL) quenching could be explained by Foerster resonant
energy transfer “NC→porphyrin”, more than 85% of the PL quenching is
caused by the other reason. It was shown that at the same molar ratios x =
[H2P(m-Pyr)4]/[NC], the quenching is more effective for small NCs than for larger ones. Based
on the comparison of experimental Stern-Volmer quenching plots I 0 / I ( x) and quantum
mechanical calculations for the electron single-carrier wave functions, we conjecture that the
specificity of the exciton non-radiative decay in “NC-porphyrin” nanocomposites is due to the
manifestation of inductive and mesomeric effects leading to the charge tunnelling through the
ZnS barrier in the conditions of quantum confinement.
This work was supported by Belarus Program Nanoteckh 6.18, Volkswagen-Stiftung Grant No
I/79 435 and ECO-NET Project (program No 18905YD).
44
POSTERS
PHOTONICS OF THE NON-CONJUGATED
POLYARYLENEPHTHALIDES – NEW POLYMER CLASS
FOR ELECTROLUMINESCENCE DEVICES
V.A. Antipin1, A.N. Lachinov2, A.S. Nakaryakov2,
S.N. Salazkin3, A.A. Kovalev2, V.P. Kazakov3
1 - Institute of Organic Chemistry URC RAS, Ufa, Russia
2 - Institute of Physics of Molecules and Crystals URC RAS, Ufa, Russia
3 - Institute of Elementoorganic Chemistry RAS, Moscow, Russia
lachinov@anrb.ru
Optical properties of the new polymer class, namely, polyarylenephthalides, are discussed in this
paper. This polymers are known as a substances which demonstrate different electrical effects.
The main condition for this phenomenon is one dimension of the experimental devise must be no
greater than Debye wavelength for this material. This electrical effect is electrical switching
induced by different physical fields (electrical, magnetic fields, temperature and pressure) [1].
During this phenomenon high conductivity state appears in the insulator film. This conductivity
depends on the external actions. Bipolar injection of charge carrier in to thin films permits to
realize electroluminescence (EL). Spectrum of this EL emission coincides with the
photoluminescence spectrum in this case. But the mechanism of this photoluminescence is not
clear. Thus, in this paper the results of the optical properties investigation are presented. The
investigation is based on the analyze of the photoluminescence spectrum, phosphorescence,
excitation spectrum and adsorption spectrum. Influence of the excitation energy on the spectrum
has been studied. It is observed that shift of the excitation wavelength at 200 nm results in shift
of the emission band at 160 nm to the red zone (fig. 1).
This phenomenon demonstrates possibility of the energy properties of the injection to manage
the wavelength in case of the EL. Possible mechanisms of changing the polyarylenephthalides
optical properties by UV-illumination are discussed in the report.
Radiation
wavelength,
nm
Excitation wavelength, nm
Fig. 1. Dependence of the radiation wavelength in the excitation wavelength. Percentage of the
PPB 1.2% in the methylene chloride
45
MODELING OF NONLINEAR-OPTICAL ACTIVITY
OF POLYMER ELECTRET AND RELAXATION STABILITY
OF ITS QUADRATIC RESPONSE
M.Yu. Balakina
A.E. Arbuzov Institute of Organic and Physical Chemistry, Kazan SC RAS, Kazan, Russia
marina@iopc.knc.ru
Polymer material exhibiting electrical response due to the incorporated organic dipole
chromophores is in the electret state resulting from the orientation of chromophore groups in the
applied electric field. Material in the electret state is characterized by the macroscopic
polarization which is determined by the orientational order of the chromophores. In the polymer
electret organic chromophores are in the locally anisotropic polarizable deformable environment.
It is necessary to elaborate new models and approaches for the description of the medium effect
on the chromophore nonlinear optical (NLO) response.
In [1-3] we have proposed original analytical approach to the modeling of polymer electret NLO
response, which is based on the special ansatz defining the cavity occupied by the chromophore
in the material. The cavity is chosen to be conformal to the characteristic ellipsoid of the
generalized permittivity tensor of the material, virtual medium inside the cavity being either
isotropic or anisotropic. In the framework of the model the local electric field affecting the
chromophore in the electret is obtained. This field depends on the applied electric field,
macroscopic polarization of the electret, dielectric properties of the medium, as well as on the
chromophore electric moment, multipole (quadrupole and octupole) contributions being taken
into account in addition to the dipole contribution. The obtained equation establishes relationship
between the electret macroscopic polarization and molecular electric characteristics of the
chromophores (dipole moment, polarizability and hyperpolarizability). Analytical equations for
the pyroelectric, piezoelectric and electrostrictive coefficients of the material are obtained on
basis of polymer electret macroscopic polarization.
To study the stability of the polymer NLO electrets quadratic response, which is directly
connected with the relaxation of chromophores orientation order, we have suggested an
evolutional model accounting for the interrelation of electric, rheological and thermal processes
in polymer material. The distinguishing feature of the model is the use of non-stationary
equations taking into account pyroelectric, piezoelectric and electrostrictive effects [2, 3].
Retardation of the response is described by the integro-differential operators of the special type;
one of the models uses the so-called Kohlrausch-Williams-Watts extended exponents. The main
attention is given to the relaxation model of two-dimensional polymer film.
[1]. M.Yu. Balakina. Chem Phys Chem 2006, 7, 2115-2125;
[2]. M.Yu. Balakina. J Non-Cryst Solids 2007, 353, 4432-4436;
[3]. M.Yu. Balakina. Russ Chem Bull 2008, 57, №7, 1-5.
The work is performed under financial support of Russian Foundation for Basic Research
(projects № 08-03-01108-а and № 09-03-00696-а).
46
CONTINUUM MODEL FOR ELECTROSTATIC ENERGY OF
INTERACTION OF A DIPOLAR ION OR DIPOLAR MOLECULAR
SYSTEM IMMERSED IN A SPHERICAL NANOPARTICLE
M.V. Basilevsky1, E.A. Nikitina2, F.V. Grigoriev3, M.V. Alfimov1
1 - Photochemistry Center RAS, Moscow, Russia
2 - Institute of Applied Mechanics RAS, Moscow, Russia
3 - Research Computing Center, Moscow State University, Moscow, Russia
basil@photonics.ru
A method for a theoretical calculation of the electric response field, generated in a spherical
nanoparticle after immersion in it a dipolar ion or dipolar molecular system was elaborated. The
new algorithm for solving the Poisson's equation, implemented and tested in the Photochemistry
Center, Russian Academy of Sciences was applied. It focuses on the study of electrostatic effects
of polarization and interaction in non-inform continuous dielectric medium. The non-uniformity
of the environment is introduced as a variable dielectric permittivity of the medium. For simple
objects (a spherical ion and a two-sphere dipole) a dependence of implantation of free energies
on the particle position and orientation within the nanoparticle is calculated. These energetic
profiles show a singularity (a deep narrow well) in passing through the surface of a nanoparticle.
Similar calculations are performed for several polar molecules, and for a typical organic dye.
Under financial support of RFBR 07-03-00479-а
47
OPTICAL CONTROL OF NANOPOROUS POLYMERS SYNTHESIS
PROCESS FROM PHOTOPOLYMERIZABLE COMPOSITES
M.A. Batenkin, A.N. Konev, S.N. Mensov, S.A. Chesnokov
G.A. Rasuvayev Institute of Organometallic Chemistry RAS, Nizhny Novgorod, Russia
mensov@iomc.ras.ru
As a rule, photopolymerizable composites (PPC) contain non-polymerizable compounds. The
most of organic solvents are not compatible with three-dimensional polymers synthesized from
the PPC based on acrylic oligomers. Considerable quantity of non-polymerizable compounds in
the PPC mixture can result in micro- and nanoscaled ruptures of polymeric net due to oligomer
and solvent true solution transforming into polymer-solvent heterogeneous medium.
Consequently, nanopores can be formed in the volume of polymeric glass during the PPC
hardening in the presence of solvent [1]. The porous polymer can be used both, as a filter for
gases and liquids and as a material for visible and infrared optics. The cavities in volume of the
nanoporous polymer can be filled, for example, by inorganic component with high refractive
index. This allows to produce material with high optical density. The size and morphology of the
pores depend on concentration and chemical nature of non-polymerizable additive, as well as on
the polymerization reaction rate. The last one can be controlled by the intensity of influencing
light upon the photoinitialization.
In this paper the influence of initiating radiation intensity on nanoporous polymeric structure
synthesized from the PPC is under investigation. The PPC based on oligoether(meth)acrylate
OCM-2 was used for experimental research. Polymeric structures formed during the
photopolymerization process were analyzed by the method of atomic-force microscopy and
microscopes Solver P47 and Smena-A were used. A porous structure forms in the volume of the
polymer if concentration of the solvent is more than 20 – 25 mas.% (for methyl alcohol
additive). The most homogeneous structure with the minimal size of pores (~ 200 – 300 nm)
forms if content of non-polymerizable compound is about 30 mas.%. The size of pores enlarges
with the solvent content increase. We studied the
intensity influence on morphology of forming pores for ρ, nm
400
the following conditions: concentration of methanol in
PPC was 30 mas. % and intensity was varied in the range
200
from 1 kLx to 50 kLx. The size of formed pores is
obtained to be non-monitonically dependent on the
0
intensity (fig. 1). There is an optimal value of influencing
30
I, kLx
0
10
light intensity, when the porous structure is the most
Fig.1 – Dependence of the pores size ρ on
homogeneous and the size of pores is minimal
the intensity I.
(~ 200 nm).
This work was supported by the RFBR (grant №№ 08-03-12090, 08-03-97055 and
09-03-00668).
[1] Batenkin M.A., Konev A.N., Mensov S.N., Chesnokov S.A. Nanostructuring of polymers
upon photopolymerization in the presence of neutral component // The third international
school of chemistry and physical chemistry of oligomers. Moscow – Chernogolovka –
Petrozavodsk, June 2007, p. 61.
48
SYNTHESIS, SELECTIVE AND PHOTOLUMINESCENT PROPERTIES
OF THE DERIVATIVES OF TERPYRIDINES - EFFECTIVE
MOLECULAR RECEPTORS FOR ZINC(II) ION
V.E. Baulin, N.M. Logacheva, A.M. Safiulina, N.Y. Konstantinov, A.Y. Tsivadze
A.N. Frumkin Institute of Physical Chemistry & Electrochemistry, Moscow, Russia
baulin@phyche.ac.ru
In present time the correlation between concentration of "ions of a life" in the cells of live
organisms and occurrence of the certain pathologies is established. In particular, it is proved, that
ions Zn2+ provide the important biological functions in cells and lifetime measurement of their
concentration allows spending early diagnostics of some diseases. One of the ways of
measurement of concentration of ions Zn2+ in vivo is the use of the opportunities of fluorescence
with application of the organic fluorescenting receptors, which capable selectively to connect
ions Zn2+ at surplus of ions Na+, K+, Mg2+ and Ca2+, and spectral-kinetic characteristics of
fluorescence of free and connected of the receptor ions Zn2+ should provide an opportunity of
quantitative measurements under physiological conditions. Besides these compounds must
possess the low photo-toxicity and comprehensible solubility in physiological environments.
In the present work we developed an effective method of synthesis earlier not described
derivatives of 2,2':6',2"- terpyridines (I-V), possessing by additional coordinating fragments of
crown-ethers and o-phosphorylphenols, that opens opportunities for purposeful designing
metalocomplexing supramolaculary systems with the necessary fluorescenting properties.
R
The structure of compounds (IV) is confirmed by the NMR
1
Н and 31Р spectroscopy and
the element analysis. For
compounds (IV) it is executed
the X-Ray analysis.
The primary testing of the
N
N
N
ability of (I-V) selectively to
I-V
connect ions Zn2+ was spent by
a method of the liquid
O
O
O
O
extraction from the modeling
I, R=NH2; II, R= O
III, R= O
physiological solutions. The
O
O
O
O
concentrations of ion Zn2+in
O
O
the initial and equilibrium
OH
OH
solutions were determined by
O
IV, R=
N
inductively coupled plasma
V, R=
N
N
P
N
O
mass-spectrometry (ICP-MS).
P
Ph
Ph
Ph Ph
For the most perspective
compounds the parameters of spectra of absorption and a luminescence as function of
concentration of the ions Zn2+ have been investigated. The set of the extraction measurements
and characteristic changes of spectra of absorption and emission allows to consider, that
derivatives of 2,2':6',2"- terpyridines (I-V) can be used for creation of selective photoluminescent
molecular receptors for definition of ion Zn2+ in physiological environments.
Work is executed at financial support of the program of basic researches of Presidium of the
Russian Academy of Science «Development of methods of reception of chemical substances and
creation of new materials» and the Grant of the RFFI № 09-03-01208-á
49
PHOTOLUMINESCENT PROPERTIES
OF FLUORENE-SUBSTITUTED PORPHYRINS
A.Yu. Chernyadyev, Yu.A. Plachev, A.Yu. Tsivadze
A.N. Frumkin Institute of Physical Chemistry & Electrochemistry, Moscow, Russia
chernyadyev@mail.ru
Complexes of metals with porhyrins of different structure can be applied as active components
of electronooptic devices (photovoltaic convertors, electroluminescent devices) and systems for
singlet dioxigene generation. New complexes of transition metals (Ni, Pd, Pt) and nontransition
metals (Mg, Al) with fluorene-substituted porphyrins have been prepared. Influence of metal
nature on the luminescent properties of tetrapyrrolic core of metal fluorene-substituted
porphyrins have been estimated. It was found magnesium and aluminum fluorene-substituted
porphyrins manifest more intensive fluorescence as compared of free base porphyrin and can be
promising components of red light emitted elecrofluorescent devices. Palladium and platinum
fluorene-substituted porphyrins manifest weak fluorescence as compared of starting free base
porphyrin due to enhancement of IC transitions by heavy atoms of palladium and platinum.
These compounds can be perspective as active components of electrophosphorescent devices and
can be active in singlet dioxygen generation process.
The work was supported by RFBR grant № 07-03-13547 and ISTC project “Development of
Materials and Processes for High Technology Organic Devices”.
50
PHOTOCHROMISM OF MEROCYANINE COMPLEXES
OF DIPHENYLOXAZOL CONTAINING SPIROPYRANS
WITH TRANSITION METAL CATIONS
A.V. Chernyshev1, A.V. Metelitsa1, E.B. Gaeva1, N.A. Voloshin2, V.I. Minkin1
1 - Institute of Physical and Organic Chemistry, Southern Federal University,
Rostov-on-Don, Russia
2 - Southern SC RAS, Rostov-on-Don, Russia
anatoly@ipoc.rsu.ru
The mechanism of photochromic rearrangements of spiropyrans is related to thermally and
photochemically reversible heterolytic cleavage of Сspiro-О bond of cyclic isomer A followed by cis-transisomerisation into metastable merocyanine form. The presence of partial negative charge on the oxygen
atom of merocyanine isomer makes it potential ligand in complexation reactions with metal ions [1]. One
of the deactivation pathways of complexes excited states is their photodissociation into spiroform of
ligand and a metal cation [2]. This phenomenon opens vast perspectives of spiropyran application in new
fields. For example, it makes possible to control the process of target species binding in the sample with
active surfaces of chemical sensors ‘on-line’ [3]. However, no literature is available on the quantitative
estimation of the efficiency of complex photodissociation.
Recently, it has been shown that in solutions,
R1
1
R = H, Cl, OCH 3 spironaphthopyrans having diphenyloxazol substituent in the
position 5’ form stable complexes of merocyanine isomer with
N O
N
Ph
transition metal cations [4]. It has been revealed that such
R2
R2 =
O
Ph
complexes exhibit photochromic properties. Irradiation of
complex solutions with visible light induces their thermally reversible decoloration (fig. ). After switching
off the irradiation source the system reverts to the initial equilibrium position. In this case the observable
thermal relaxation rate constant is the same as the rate constant of complex formation. Therefore, it may
be concluded that a photodissociation process takes place.
Photodissociation reaction of complexes can be described
light "on"
α
by the followed equation:
1,0
dα
−
= I MB Φ − k ∆ (1 − α )
dt
0,8
where α − complex molar fraction, k∆ - complexation rate
constant of pseudo-first order, Ф – quantum yield of
0,6
photodissociation, IMB – intensity of the absorbed light.
On the basis of the equation the values of
0,4
"light "off"
photodissociation quantum yields of Zn2+ and Cd2+
merocyanine complexes has been calculated to be 0.040,2
0.15.
0,0
This work was supported by the Ministry of education
and science of Russian Federation (project No
DSP.2.2.2.3.16008) and RFBR (project No 09-03-00813).
0
50
100
150
200
250
300
t, s
References:
1. Alfimov M.V., Fedorova O.A., Gromov S.P. // J. Photochem. Photobiol. A: Chem. 2003. Vol. 158.
P.183–198.
2. Chibisov A.K., Görner H. // Chem. Phys. 1998. Vol.237. P. 425-442.
3. Radu A., Scarmagnani S., Byrne R., Slater C., Lau K. T., Diamond D. // J. Phys. D: Appl. Phys.
2007. Vol. 40. P. 7238-7244.
4. Chernyshev A.V., Voloshin N.A., Raskita I.M., Metelitsa A.V., Minkin V.I.// J. Photochem.
Photobiol. A: Chem. 2006. 184. P. 289-297.
51
MECHANOCHEMICAL PREPARATION
OF WATER-SOLUBLE COMPLEXES OF CAROTENOIDS
V.I. Evseenko1, E.S. Meteleva1, A.V. Dushkin1, N.E. Polyakov2
1 - Institute of Solid State Chemistry and Mechanochemistry SB RAS, Novosibirsk, Russia
2 - Institute of Chemical Kinetics and Combustion SB RAS, Novosibirsk, Russia
evseenko@solid.ncs.ru
Carotenoids are a class of pigments widespread in nature. Carotenoids are widely used as food
dyes and biologically active additives, but their application is restricted by insolubility in water
and low stability.
Among the methods of the preparation of water-soluble forms of biologically active compounds
the most well-known are the formation of intermolecular complexes with cyclodextrins, more
often with β-cyclodextrin. Also it is known the method of preparation the colloid dispersions and
emulsion of carotenoids, which include dissolution carotenoids at the increased temperature in
organic solvents in the presence of surface-active substances. Imperfection of these methods are:
• Necessity of preliminary dissolution carotenoids in toxic organic solvent and the subsequent
extraction of the formed complexes.
• Significant duration of process, necessity of use of the expensive equipment and frequently
recycling of waste products of the used solvents.
• All received compositions are not dissolved in water, but form insufficiently stable water
dispersions or emulsion which can be removed by usual filtration.
The method of complex preparation used in the present work was a mechanochemical treatment
of the solid mixture of carotenoid crystals with arabinogalactan powder. Typical
mechanochemical reactions are those activated by co-grinding or milling of powder materials.
As a complexant we used arabinogalactan - natural polysaccharide extracted from the Siberian
larch and the Gmelin larch. The preparation and properties of similar complexes are described in
[1, 2]. During mechanochemical treatment carotenoid molecules penetrate to arabinogalactan
matrix from its initial crystal state, forming the solid solution representing disordered solid phase
in which carotenoid and arabinogalactan molecules undergo non covalent not ionic interactions.
During dissolution of this solid dispersion the complexes keep their structure.
It was shown that formed nanosized complexes have essential advantages as compared with
initial carotenoid. In particular, it was demonstrated a substantial increase in solubility of
carotenoids (concentration of beta-carotene in the aqueous complex solution was approximately
2.5 g/l). The fact of significant increase of solubility carotenoid in mechanochemically prepared
complexes is inherent to arabinogalactan and, according to the literary data, unknown or is
absent for others complex-forming compounds.
High stability of the radical cations of carotenoids in nanosized complexes polysaccharide
arabinogalactan opens wide opportunities for application of these complexes for design of
artificial photosynthetic and photocatalytic devices.
1. Patent RF № 2006143081. A water-soluble medicinal composition and method of its
preparation. T.G.Tolstikova, G.A.Tolstikov, A.V.Dushkin, E.S.Meteleva.
2. A. V. Dushkin, E. S. Meteleva,T. G. Tolstikova,G. A. Tolstikov, N. E. Polyakov, N. A.
Neverova, E. N. Medvedeva, and V. A. Babkin. Mechanochemical preparation and
pharmacological activities of water-soluble intermolecular complexes of arabinogalactan with
medicinal agents // Russian Chemical Bulletin , International Edition , Vol. 57, № 6, p. 1-9.
52
EFFECT OF THE CHROMOPHORES MUTUAL ORIENTATION
ON NONLINEAR-OPTICAL RESPONSE OF MOLECULAR SYSTEM.
QUANTUM-CHEMICAL CALCULATIONS
O.D. Fominykh, M.Yu. Balakina
A.E. Arbuzov Institute of Organic and Physical Chemistry, Kazan SC RAS, Kazan, Russia
fominykh@iopc.knc.ru
Interest in new polymer materials, whose nonlinear-optical (NLO) properties are determined by
incorporated organic chromophores, is conditioned by their potential application in photonics
and optoelectronics. The optimization of polymer material NLO properties requires thorough
investigation of the effect of the chromophore groups mutual arrangement. We considered
molecular systems with various ways of chromophores organization. The structure of clusters
from two and three molecules of p-nitroaniline (PNA), coupled by the hydrogen bonds, thus
promoting the increase of the system dipole moment, are investigated [1]. On the basis of
performed quantum-chemical calculations of the clusters the cooperative effect was established
at the formation of first hyperpolarizability (β): β of dimer increases 2.6 times, and β of trimer 5.1 times as much as that of single chromophore. Additional increase of β is achieved by means
of the solvent effect, accounted in the framework of the polarizable continuum model (PCM).
To study the bearing chain conformation effect on the NLO response of the attached
chromophore the hyperpolarizability of dimer on the basis of diglycidyl ether of bisphenol-A
with dimethylaniline in each unit of the chain was evaluated. Characterististic conformations
were selected in the course of conformation search by Monte-Carlo method [2]. The dimer β||
was established to exceed β|| of the chromophore fragment by ~70% due to mutual arrangement
of the chromophores (the angle between them being ~60°).
One of the ways of optmization of quadratic NLO properties of polymer material is the limitation
of the possiblility of antiparallel arrangement of the chromophore groups, resulting in substantial
decrease of the NLO effect. Creation of polymer materials on the basis of cross-linked
dendrimers and hyperbranched polymers with dendrite groups is quite promissing in this
connection. We calculated structure and hyperpolarizability, β, of model oligomers of dendrite
type - bidendrons and tridendrons – with various unit lengths, containing different chromophore
groups. The effect of linking the oligomer branches on its NLO characteristics was studied by
the example of model non-cross-linked and cross-linked bidendrons on basis of
dimethyldioxymethane with (4-dimethylamino-3’-oxymethyl-4’-nitro)azobenzene chromophore
group in each branch, hexamethylenediisocyanate being used as cross-linking agent.
The oligomer dipole moment was established to increase almost twice at cross-linking, due to
decreasing the angle between the chromophores (by ~23°). Polarizability αav and the values β||
increase in the series chromophore - non-cross-linked oligomer - cross-linked oligomer, their
values being 32.4⋅10-24 esu, 79.7⋅10-24 esu, 91.2⋅10-24 esu, and 36.7⋅10-30 esu, 41.1⋅10-30 esu,
46.4⋅10-30 esu, respectively.
Electric characteristics – dipole moment and molecular polarizabilities of the studied systems –
were calculated by TDHF/AM1 method using GAMESS programme.
[1]. M.Yu. Balakina, O.D. Fominykh// Int.J.Quant.Chem., 2008, 108, 2678;
[2]. M.Yu. Balakina, O.D. Fominykh, F. Rua, V. Branchadell// Int.J.Quant.Chem., 2007, 107,
2398.
The work is performed under financial support of Russian Foundation for Basic Research
(projects № 08-03-01108-а and № 09-03-00696-а).
53
INFLUENCE OF THE ORGANIC LIGHT-EMITTING DIODE
STRUCTURE ON THE IR(PPY)3 ELECTROLUMINESCENCE
R.M. Gadirov, K.M. Degtyarenko, N.S. Eremina, T.N. Kopylova
Tomsk State University, Russia
kopylova@phys.tsu.ru
In the last few years it has been demonstrated that the use of phosphorescent organic materials in
organic light-emitting diodes is promising due to the special features of excitation of their
luminescence in an electric field []. The iridium complex Ir(ppy)3 is undoubtedly one of the
promising electrophosphorus compounds [].
This work presents results of investigations into the influence of the organic light-emitting diode
structure on the Ir(ppy)3 electroluminescence.
For the components of the electroluminescent compositions, we have chosen:
1. Ir(ppy)3 doped into polyvinylcarbasole (PVC) and polyfluorene (PFO) polymers, because the
Ir(ppy)3 luminescence in a pure film is much weaker than in compositions with a polymer,
2. PEDOT (polystyrylsulfonate-1), 3 mass% in water,
3. TPD (N,N′-bis(3-methylphenyl)-N,N′-diphenylbenzylidene),
4. Alq3 (aluminum tris-(8-oxyquinolinate)).
The organic thin-film structures were prepared by the centrifugation method. Chloroform (CLF),
chlorobenzene (CLB), and tetrahydrofuran (THF) were used as solvents. ITO was used as an
anode (100Ω/cm2), and CaMg, Mg, and Al protected by an Ag layer were used as cathodes. The
film thickness was measured with a Linnik (MII-4M) microinterferometer and a laser LÉF-757
ellipsometer. The electroluminescence spectra were registered with an Avantes CCD fiber
spectrometer, and the photoluminescence spectra were registered with an SM 2203
spectrophotometer-spectrofluorimeter and a Carry Eclipse spectrofluorimeter. The currentvoltage and brightness-voltage characteristics were registered with a special complex.
The special features of the Ir(ppy)3 photoluminescence in various compositions were
investigated. It has been demonstrated that the Ir(ppy)3 photoluminescence in PVC is caused by
its phosphorescence (with a radiation lifetime of ~0.06 ms); total excitation energy transfer from
PVC to Ir(ppy)3 was observed. The Ir(ppy)3 electroluminescence spectrum in PVC was similar to
the photoluminescence spectrum. It was demonstrated that the electroluminescence
characteristics (the threshold voltages at which electroluminescence was observed, luminescence
brightness, running current density, and stability of characteristics) depend on the nature of the
organic solvent used for film preparation, the nature of the employed film-forming polymer,
presence of additional layers at the boundary with the electrodes, and the cathode material.
The most promising electroluminescent structure has been established: ITO/PEDOT/PVC:
Ir(ppy)3/LiF/CaMg/Ag.
54
MODEL OF ENERGY CONVERSION EFFICIENCY
FOR POLYMER PHOTOVOLTAIC CELLS
D.Yu. Godovsky1, O. Inganas2
1 - Laboratory of Physical Chemistry of Polymers, INEOS RAS, Moscow, Russia
2 - IFM, Linkoping University, Linkoping, Sweden
dmigo@yandex.ru
Here we present the calculation of the upper limits of energy conversion efficiency for D-A
based polymer solar cells. There are a number of differences between D-A based polymer PV
cells and the p-n junction based semiconductor ones:
1. Conjugated polymers are regarded to be one-dimensional semiconductors, hence the density
of states for 1-D polymer differs dramatically from the density of states of 3-D semiconductor
which is used for standard calculation of energy efficiency for semiconductor PV-cells. The
dramatic difference in absorption coefficient dependence on photon energy determines the
difference in the optimum for the efficiency of energy conversion
2.Practically all the authors calculating the efficiency of p-n junction cells assume the
equilibrium emission from the photoexcited states of the semiconductor. This assumption is not
valid from our point of view for D-A based polymer PV cells, due to two factors:
First and the most important is that for D-A combinations, as in the case of
polyphenylenevinylene(PPV)/C
60 for example, the ultrafast non-radiative transfer takes place
-13
with the time constants ca 10 sec., which is around two orders of magnitude faster, than the
characteristic time for spontaneous emission from PPV. This causes luminescence quenching
and totally destroys the equilibrium between photons in radiation subsystem and electron
subsystem of the PV cell. The stability of this charge transfer extends up to ms, and reversibility
is not an appropriate model. Therefore the D-A PV cells work under non-equilibrium condition
and all the formulae obtained using thermodynamics principles like in Shokley-Quessier model
are not valid in this case.
3. The third distinctive feature of D-A PV cells is the use of thin layers of polymers (10-300 nm),
mainly because of the low charge mobility. The condition of thickness of the cell, which is
assumed by most models, calculating the efficiencies of power conversion, is not the case for
polymer cells.
We made the calculations of the photovoltaic polymer cells efficiencies, assuming that the
plastic D-A solar cells work simply as photon counters, and the energy of individual photon is
not to be taken into account due to the very nature of the D-A transfer. The open circuit voltage
to be considered is determined simply by the difference between the LUMO of donor and
HOMO of the acceptor minus some part obtained theoretically, and the very fact of the D-A
transfer “equalizes” the energy input from each photon, independently of it’s energy. The
optimal value of Voc for given acceptor molecule can be calculated from the analysis of three
energy level diagram: HOMO of conjugated polymer (E1), LUMO of polymer (E2) and HOMO
of acceptor (E3).
We used 1-D Density of States model, ideal lorentzian absorber model and some intermediate
case. The results, obtained using the latter model (without correction for fill factor reduction)
give the limit to efficiency of D-A plastic solar cell ca.17% in single band gap approximation.
The drastic increase of the efficiency with the increase of absorbance peak width is associated by
us with natural “multi-bandgap” phenomena, arising from the fact that the band gap value of
most spin cast polymers varies due to the natural dispersion of conjugationlength.
55
PHOTOPHYSICAL PROPERTIES OF AQUEOUS SOLUTION
OF 3,3’-DIETHYLTHIACARBOCYANINE IODIDE
IN THE PRESENCE OF CUCURBIT[7]URIL
D.V. Golubkov, D.A. Ivanov, N.Kh. Petrov, M.V. Alfimov
Photochemistry Center RAS, Moscow
retmas@gmail.com
Fig. 1. Cyanine dye DTCI
Fig. 2. Cucurbit[7]uril molecule
Fig. 3. a – water solution of DTCI,
b – at presence of CB7
Photophysical properties of aqueous solution of cyanine
dye (DTCI, 10-7 M) (fig. 1) was studied in the presence
of cucurbit[7]uril (CB7) (fig. 2) by means of optical
spectroscopy. Pumpkin-shaped macrocycle of CB7 has a
rigid intermolecular cavity that determines its behavior as
host-molecule. It allows including DTCI as the guestmolecule. The molecular dimensions of CB7 are as
follows: the internal and external diameters are at 5.4 Å
and 7.3 Å, respectively, the height at 9.1 Å [1].
It was found that upon addition 0.1mM of СВ7 in
solution, DTCI absorption essentially changed (fig. 3).
Assuming formation of host-guest complexes (1:1), we
have determinated the associated constant К=2. 8 104 М-1,
varying concentration of СВ7 and measuring absorption
at 550 nm. Measurement of polarization of DTCI
fluorescence has shown an essential increase in the
effective volume of radiating molecules in the presence
of СВ7. It is in a good agreement with the assumption of
producing host-guest complexes.
It was found that lifetime of DTCI fluorescence inside
СВ7 increases 6 times in comparison with a
homogeneous aqueous solution; it so doing quantum
efficiency of the nonradiating relaxation of the electronicexcited molecules of the DTCI in СВ7 increases
approximately 8 times.
Work was partially supported by the RFBR, the
grant 07-03-00479.
REFERENCES
J.W. Lee, S.Samal, N. Selvapalan, H-J. Kim, K. Kim, Acc.Chem.Res. 2003, vol.36, 621.
56
TRIPLET-TRIPLET ENERGY TRANSFER
IN NANODIMENSIONAL MOLECULAR LAYERS
N.Kh. Ibrayev, A.K. Aimukhanov, E.V. Seliverstova
Karaganda State University, Kazakhstan
nibraev@ksu.kz
Triplet-triplet energy transfer was investigated in the multilayer films. Aromatic molecules have
been used as energy donors. Amphiphilic molecules of dyes served as energy acceptors. Triplet
energy donors had high quantum yield of intersystem crossing S1→T1. The filling of acceptor
triplet states was not observed at direct excitation. Thin films of the energy donor have been
received on a surface of nonluminescent quartz substrate by vacuum deposition or by LangmuirBlodgett (LB) method. Dye monolayers were deposited by LB method on the surface of donor
film. The number of the monolayers varied from 1 to 10. Measurements of donor and acceptor
decay of the delayed luminescence were performed by photon-counting mode. Excitation was
performed by N2−laser pulses in the energy donor absorption band. The measurements were
performed at sample temperature Т = 90 К.
While exciting in the anthracene absorption band, the bands of annihilation delayed fluorescence
(DF) of the anthracene monomers (λmax = 500 nm) and excimers (λmax = 500 nm) were observed
for pair anthracene−nile red. Besides, the band of sensitized DF of nile red was observed (λmax =
650 nm). The increase of the dye concentration in monolayer leads to quenching donor
luminescence and to increase of acceptor DF intensity. Kinetics decay of the donor and acceptor
luminescence has complicated form. The initial part of the kinetics decay curves is described by
power function and long-time part by exponential function. Power function exponent of kinetics
initial part of the donor annihilation DF is increase with the increase of the acceptor
concentration. Kinetics decay of acceptor sensitized luminescence also depends on dye
concentration. The increase of the anthracene concentration in monolayer leads to increase of
intensity of acceptor. The highest radiation yield of acceptor is observed at donor concentration
50-60 molar %. Similar data are received and for pairs anthracene-rhodamine B and 1,2benzanthracene-rhodamine B.
Distance influence between layers of the donor and acceptor on energy transfer efficiency was
studied. Separation of donor and acceptor layers was performed by layers of palmitic acid. The
intensity of donor luminescence increases twice with increase in distance from 0 Å to 54 Å for
the pair 1,2- benzanthracene-rhodamine B. The intensity of anthracene DF increases in 1.8 times
at separation of anthracene and rhodamine B layers by 6 monolayers of polyampholytic polymer.
The temperature influence on energy transfer was investigated. It is shown, that energy transfer
efficiency between layers of the donor and acceptor depends on migration rate of donor exciton
as a result of inhomogeneous broadening of donor molecules.
The influence of external magnetic field on the property of the delayed luminescence donor and
acceptor has been studied for ascertainment of a nature of sensitized luminescence of dyes. The
limit value of the negative magnetic effect on DF of donor at 0.5 T is equal 16.3% for pair
anthracene-rhodamine B. Magnetic field influences on the intensity of dye sensitized
luminescence in a lesser degree. Maximal value of rhodamine B magnetic effect is 11.3 %.
Influence of external magnetic field on dye sensitized luminescence is evidence of that the
luminescence is the result of triplet-triplet exciton annihilation.
57
SPECTROSCOPIC PROPERTIES OF LANGMUIR FILMS
OF RHODAMINE DYES AND POLYAMPHOLYTIC POLYMER
N.Kh. Ibrayev1, Zh.K. Smagulov1, V.I. Alekseeva2, L.E. Marinina2, L.P. Savvina2
1 - Karaganda State University, Kazakhstan
2 - Organic Intermediates and Dyes Institute, Moscow, Russia
nibraev@ksu.kz
Nanodimensional films on a basis of amphiphilic molecules of rhodamine dyes (heptadecyl
either of rhodamine B - dye I; 3,6-bis(octadecylamino)-9-o-carboxiphenyl) xanthyl perchlorate dye II) and hydrophobic-modificated polyampholytic polymer have been received by LangmuirBlodgett (LB) method. Mixed monolayers were formed at water–air interface using Langmuir
trough. Monolayers were transferred onto quartz substrates by vertical dipping according to Z
and Y types transfer at surface pressure of π=30 mN/m and the dipping speed through the
monolayer 0,02 mm/s. The thickness of the films consisted of 20 monolayers.
Absorption and fluorescence spectra of LB films from dye I are measured at various ratio of dye
and polyampholyte molecules. The shape and position of the absorption bands of the dye LB
films indicates on the formation of mainly plane dimers with a small number of sandwiches
dimers. The existing of monomers also is visible. Decreasing of dye concentration in LB films
leads to decreasing of the probability of both plane and sandwich dimers formation. The changes
observed in the fluorescence spectra confirm these assumptions. The long-wave shift of
maximum fluorescence band in comparison with monomeric emission is indicated, that
fluorescence in LB film corresponds to a radiative transition from the lower excited level of
plane dimers. Dye II molecules also participate in aggregation processes that leads to
deformation of absorption and fluorescence spectrum in comparison with its ethanol solution
spectrum. The ratio between the intensities of the short-wave and long-wave absorbance maxima
of dye II is higher than that of dye I. The fluorescence spectra of dye II LB films consist of one
band, which slightly broadened, but with similar shape and maximum position compared to
ethanol solution.
LB films with addition of stearic acid (SA) molecules have been received for the purpose of
modification of films structure. The polymer concentration in three-component monolayers was
a constant (33 mol%), and a dye and SA ratio changed in following proportions: 11:55, 22:44,
33:33 mol%. Study of phase states on a subphase surface has shown, that three-component
monolayers are in more condensed state in comparison with two-component monolayers, that
specifies in more compact molecules arrangement in a monolayer. It is observed two maxima in
absorption spectra of dye I LB films: the most intensive corresponds to a monomeric band, shortwave, shown in the form of a shoulder, denotes the presence of «sandwich» type dimers in the
film. There are two maxima in the dye I fluorescence spectra – monomeric (λmax=585 nm) and
dimeric (λmax=610 nm), which are clearly defined in comparison with two-component films. The
intensity of monomeric band is decrease with increasing of SA concentration in LB film, and the
long-wave dimer band becomes more intensive. Presence of monomers and aggregates for threecomponent films of dye II also is characteristic.
58
NEW BLUE- AND GREEN-LIGHT-EMITTING
ELECTROLUMINESCENT POLYFLUORENES WITH 7,8,10TRIARYLFLUORINE AERIAL FRAGMENTS IN BACKBONE
M.L. Keshtov1, D.A. Lypenko2, S.I. Pozin2, E.I. Maltsev2
1 - A.N. Nesmyanov Institute of Organoelement Compounds RAS, Moscow, Russia
2 - A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
keshtov@ineos.ac.ru
Over the last few years, efforts were focused on the manufacture of emitting and blocking layers
based on new polymers with efficient conductivity and photoluminescence to be used in
electroluminescent structures. In order to form desired electroluminescent layers we had to
prepare blue-emitting polymers soluble in chloroform. At the initial stage, an attempt at
synthesizing polymers with improved electron-hole conductivity and liquid-crystalline structure
succeeded in obtaining new fluorine-based copolymer that revealed high solubility in non-polar
solvents and film-forming properties:
O
+
Ar
Ar
-2CO
O
H17C8
C8H17
H17C8
V(a-d)
IV
где
(a) ,
Ar =
H17C8
n
C8H17
(b) ,
(c) ,
(d)
C8H17
Tg values of the polymers varied within 280 – 310° С depending on the chemical structure of
monomers. Thermogravimetric analysis showed high thermal stability under argon atmosphere
as well as in air. Their weight loss did not exceed 10% within 570-580°С. Blue fluorescence
spectra had maxima in the range 340 – 420 nm. The polymers exhibited liquid crystalline
properties that made them suitable media for the formation of oriented J-aggregate structures. A
start has been made on the investigations of polymer/nanocomposite and polymer/J-aggregates
interface properties with J-aggregates aligned normally to the interface.
In summary, by finely optimization the contents of various aromatic fragments, we successfully
prepared a series of blue-light-emitting copolymers that are particularly well suited as active
light-emitting polymer media to form oriented J-aggregate structures.
This work was supported by the International Scientific and Technical Center (project no. 3718).
59
[C60(CN)5]-: A REMARKABLY STABLE [60]FULLERENE ANION
E.A. Khakina1, P.A. Troshin1, D.V. Konarev1, A.S. Peregudov2,
I.V. Soulimenkov3, S.M. Peregudova2, R.N. Lyubovskaya1
1 - IPCP RAS
2 - INEOS RAS
3 - Institute for Energy Problems of Chemical Physics RAS (Branch)
eka57671232@yandex.ru
Ionic salts incorporating anions formed from pristine C60 showed exciting electrical
(conductivity and even superconductivity) and magnetic (ferromagnetism) properties. However,
these systems are hardly applicable as materials since they undergo immediate degradation in air
reacting with oxygen and moisture. To overcome this problem, some chemical derivatization
should be carried out with the fullerene sphere to enhance its electron accepting ability and thus
make possible formation of air-stable fullerene anions.
Here we will report a facile conversion of chlorofullerene C60Cl6 to the first air-stable fullerene
anion [C60(CN)5]-.
The obtained spectral data proved unambiguously that [C60(CN)5]- ion indeed has the highly
symmetrical C5V structure. Strong field-effect of five electron withdrawing CN groups stabilizes
additionally the negative charge delocalized in the cyclopentadienyl ring. Owing to such great
stabilization, the [C60(CN)5]- anion demonstrated a remarkable stability. Thus, the anion was not
protonated even by so strong inorganic acid as DCl and the parent acid C60(CN)5H was not
formed.
This finding opens wide opportunities for design of numerous air-stable salts incorporating
[C60(CN)5]- anions. Such ionic compounds might find many useful material science applications.
Moreover, new members of the family of stable cyanofullerene anions might become available
in the nearest feature. In particular, we have already observed by ESI MS air-stable fullerene
dianions [C60(CN)8(OH)2]2-, [C60(CN)9(OH)]2- and [C60(CN)10]2- and work now on their isolation
and spectroscopic characterisation.
60
SPECTRAL AND SENSING PROPERTIES
OF 9-DTAA DYE IN POLYMER MATRICES
A.A. Khlebunov, P.V. Komarov, D.S. Ionov, A.V. Koshkin,
V.A. Sazhnikov, M.V. Alfimov
Photochemistry Center RAS, Moscow, Russia
sazhnikov@yandex.ru
Molecules with intramolecular charge-transfer are the main elements of the most part of organic
photonics devices [1]. The compounds with light emission during recombination of chargetransfer existed states are used in organic light-emitting diodes, fluorescent solar concentrators
[2] and fluorescent sensor materials.
Recent investigation [3] has shown that 2,7-dimethyl-9-ditolylaminoacridine (9-DTAA)
molecule exhibits pronounced solvatofluorochromic properties related to charge-transfer
character of S1 state. This assumption have been confirmed by quantum-chemical calculations
using INDO/S with spectroscopic parametrization [4].
In this work, the fluorescence spectra of 9-DTAA in two polymer matrices were studied. The
first type of the matrices are thin polystyrene (PS) and polymethylmethacrilate (PMMA) films
obtained with spin-coating. The second type of the matrices are silicon dioxide microspheres
with 6 nm average pore size and 10 µm average diameter, which were modified with various
functional groups (Diaspher).
1b
Figure 1 – a) Fluorescence of 9-DTAA in different matrices 1 – Diaspher-Phenyl, 2 – PS, 3 - Diaspher-Diol, 4 –
PMMA, 5 - Diaspher-OH, 6 - Diaspher-C18; b) Electron micrograph of a sensor layer, c) Response of a sensor layer
(Diaspher-OH with immobilized 9-DTAA) upon exposure to ethanol vapors.
The 9-DTAA was used as a molecular indicator for preparation of sensing layers based on the
silicon dioxide microparticles. A typical sensor layer consists of substrate, binding substance,
microparticles and indicator molecules. A cover glass was used as the substrate, an acrylic latex
A70 was used as the binding substance. An electron micrograph of a sensor layer is shown in
figure 1b.
The emission intensity responses of sensor layers to the presence of vapors of ammonia,
acetone, ethanol were obtained. These analytes are known to be important for medical
applications. The response of a sensing layer based on 9-DTAA and microparticles with
functional OH groups on the surface is shown in figure 1c.
1. E.L. Aleksandrova. Phys. Тech. Semicond. – 2004. – V. 38. №. 10. P. 1153-1194.(In Russian)
2. V. Petrova-Koch, R. Hezel, R. Goetzberger. High efficient low-cost photovoltaics. Springer
2008. P. 159-176.
3. V.А. Sazhnikov, А.А. Khlebunov, М.V. Аlfimov. High Energ. Chem. – V.41. №. 1. P. 25-28.
4. L.G. Samsonovа et al. High Energ. Chem. – V.43. №. 2. P. 105-115.
61
POLYSUBSTITUTED DERIVATIVES OF PALLADIUM TETRAPHENYL
TETRABENZOPORPHYRIN. SYNTHESIS AND PROPERTIES
A.V. Khoroshutin, D.E. Chumakov, B.M. Uzhinov, A.V. Anisimov
Department of Chemistry, Moscow State University, Moscow, Russia
khorosh@petrol.chem.msu.ru
Earlier we found that palladium tetraphenyltetrabenzoporphyrin 1 can be regioselectively
brominated to benzo-rings [1],. Further studies of this reaction allowed us to synthesize both
octabromide 2 [2], and monobromide 3.
Br
N
N Pd N
N
Br
Br
Br
N
N Pd N
N
1
Br
Br
N
N Pd N
N
3
2
Br
Br
Br
Palladium catalyzed cross-coupling reactions yielded mono- and octasubstituted acryl and
phenyl derivatives.
R R
R
R
N
N Pd N
N
R
R
N
N Pd N
N
R
R R
4 R = CH=CHCOOEt
5 R = Ph
6 R = CH=CHCOOEt
7 R = Ph
UV-Vis and phosphorescence spectra have been studied for synthesized compounds. Both
phenyl and acryl substitution have been found to lower energy shift electronic absorption spectra
bands, the same have been found for phosphorescence. Phosphorescence quantun yields have
been measured relative to 1.
This study was supported by RFBR (Grant No.09-03-00550-а)
References
1. Khoroshutin A. V., Vinogradov S. A., Wilson D. F. // ACS National Meeting. 1998. P. 49.
Dallas, TX, US.
2. Khoroshutin A. V., Chumakov D. E., Kobrakov K. E., Anisimov A. V. // Russ. J. Gen. Chem.
- 2007. - V. 77. - No. 11. -P. 1959-1964.
62
STRUCTURE AND NONLINEAR OPTICAL PROPERTIES OF BILAYER
CELLS WITH ORGANIC AND SEMICONDUCTOR NANOFILMS
COVERED BY LYOTROPIC MESOPHASE OF METAL ALKANOATES
G. Klimusheva1, Yu. Garbovskiy1, S. Bugaychuk1, A. Tolochko1, T. Mirnaya2
1 - Institute of Physics NASU, Kiev, Ukraine
2 - Institute of General and Inorganic Chemistry NASU, Kiev, Ukraine
klimush@iop.kiev.ua
Bilayer cells with organic and semiconductor nanofilms covered by lyotropic mesophase of
metal alkanoates may have great interest for applications in nanophotonics and nano-optoelectronics.
In the present work the structure of lyotropic mesophase of metal alkanoates is investigated by
X-ray diffraction technique, as well as bilayer cells with different nanofilms are studied for their
spectral and nonlinear-optical properties. To prepare bilayer cells of the first kind (i) we use
nanofilms of ionic symmetric polymethine dyes (both cation and anion types) covered by
lyotropic liquid crystal (LLC) phase of the potassium caproate in a water solution (in the weight
proportion 1:1). In the cells “dye nanofilm – LLC layer” one records thin dynamical gratings by
the interference field formed during two-wave mixing of laser pulses with nanosecond durations
(the second harmonic of Nd:YAG laser). The observed effect is differed drastically from the case
when the only dye nanofilm is present. In the later case the recording of permanent relief
holographic gratings occurs under the same experimental conditions because of heating and
evaporation of dye molecules on the interference maximums of the laser field. The use of the
LLC layer provides the dynamical character of the grating recording in the bilayer cells when the
LLC moisten the dye film and a closed contact between the film and the LLC is created. This
contact provides an effective heat diversion of the energy absorbed by the dye film to the LLC
layer that prevents heating and evaporating of the dye film. We define that the cubic resonance
nonlinearity is the main mechanism of the dynamical grating recording in the bilayer cells (i).
Nanofilms formed by deposition of different semiconductors on a support may be covered by
LLC of metal alkanoates as well. We prepare the bilayer cells based on CdSe nanofilm covered
by the potassium caprilate LLC (the cells of the second kind (ii)). We investigate spectral and
nonlinear optical properties of such cells.
63
INVESTIGATION OF DEGRADATION PROCESSES
IN ORGANIC LIGHT-EMITTING DEVICES
B.A. Kondracki, N.N. Usov, A.U. Kruchinin
JSC CRI Cyclone, Moscow, Russia
Usov-nn@yandex.ru
Organic light-emitting diodes (OLED), based on the emission of light from thin films of organic
materials in the passage of electric current through them, draw from the late 80-ies of the last
century increasing attention [1, 2].
The nanoscale structure of organic layers, that is a core of these devices, is subjected to
environment hazards. Degradation of the basic parameters of these devices in the first phase of
development based on empirical knowledge, and had descriptive character. Successes in
obtaining a stable OLED, needed to correct study of degradation processes, were associated
primarily with the protection methods active areas of devices and encapsulation methods.
Application of device construction, which includes a glass (or metal) cover with adsorbent,
allowed properly proceed to study the mechanisms of degradation depending on the devices
operation.
Experimentally it was determinated [3], that the temporal dependence of the brightness of OLED
radiation can be described by the expression:
L = L0·exp(-α·tβ),
(1)
where, α(t), β(t) – curve fitting parameters for the aging of the brightness of the radiation.
Physically, the parameter α depends on the applied voltage and operation modes (continuous or
pulse), β-reflects own material degradation due to electrochemical reactions at the boundary of
organic layers, photodegradation and degradation of anode, the curves α (t), β (t) depend on color
of light. In engineering calculations more convenient to use the dependence of the radiation
brightness OLED (L) from the current running through it (I):
This dependence is well approximated by the formula:
L=k·I.
(2)
The linearity of this characteristic is confirmed in several experimental works [4]. In the design
of OLED-devices is important to know, how the coefficient k is changed with time in order to be
able to design a scheme of correction that increases the service life of the device.
We was conducted experimental studies of degradation processes in encapsulated OLED
structures of different color light. The preparation of layers of OLED structures carried out by
vacuum thermal evaporation at pressures less than 10-6 Torr. The thickness of layers varied from
5 to 100 nm. The shadow mask used for the formation of the topology layers. Evaporation of all
layers and encapsulation of OLED structures was carried out in a on single technological cycle in
sealed boxes (MBraun), in which the contents of moisture vapor and oxygen in an inert
environment do not exceed 1 ppm.
There are discussed the characteristics of degradation time for the brightness of the various
structures of different color, the changes in the coefficient k and the sources of OLED
degradation.
Literature
1. V. Belyaev, New display technologies and their applications, Electronic Components, 2003,
№ 3, p. 26.
2. A.V. Samarin, OLED Displays: from myths to reality, Modern Electronics, 2006, № 1, p. 28.
3. H. Cloarec, D. Vaufrey, T. Mohammad - Brahim et al. Proceedings of the 27th International
Display Research Conference, Moscow, 2007, p. 215-218.
4. G. Levy, W. Evans, J. Ebner, P. Farrel, M. Hufford, B. Allison, D. Wheeler, H. Lin,. O.
Prache, E. Naviasky, IEEE Journal of Solid-State Circuits, vol. 37, № 12, p. 1886.
64
DERIVATIVES OF DIVINYLBENZOXAZOLYLBIPHENYL:
NEW ELECTROLUMINESCENT MATERIALS
T.N. Kopylova1, A.V. Kukhto2, I.N. Kolesnik2, I.N. Kukhto2, N.A. Galinovski2,
K.M. Degtyarenko2, N.S. Eremina2, R.M. Gadirov1
1 - Tomsk State University, Tomsk, Russia
2 - Institute of Physics NAS of Belarus, Minsk, Belarus
kopylova@phys.tsu.ru
Among a wide group of conjugate organic compounds, some biphenyl short-chain analogs of
polyphenylenevinylene derivatives demonstrate good stability and photoluminescent properties.
Therefore, a number of such compounds have been synthesized and the optical and
electroluminescent properties necessary for producing stable light-emitting structures have been
investigated. We investigated the compounds whose structural formulas are presented below.
N
O
N
O
N
O
S
O
I
O
O
N
II
An electroluminescent cell was created as follows. On a glass substrate with a conducting indium
and tin oxide (ITO) layer (In2O3⋅SnO2 with a thickness of 100 nm, resistance of ∼100 Ω/m, and
transparency of 95–98% in the visible range), a polythiophene (PEDOT) layer and a layer of the
corresponding examined substance incorporated into a polymeric polyvinylcarbazole matrix
(with a thickness of about 80 nm) were subsequently centrifugalized. Then a 2 × 3 mm calcium
and magnesium alloy layer with a thickness of 150 nm was deposited by evaporation in vacuum
using a VUP-5 facility. Before centrifugation and deposition of layers, the substrate with the
conducting layer was carefully washed out in organic solvents in an ultrasonic bath, and after
drying it was treated for 30 min in oxygen plasma. A negative potential was connected to the
metal electrode, and a positive potential was connected to the transparent electrode. The currentvoltage and voltage-brightness characteristics were measured using a specially developed
complex, and the electroluminescence was registered using an Avantes CCD spectrometer. The
emission spectra of organic films were investigated using a Carry Eclipse spectrofluorimeter.
The threshold electroluminescence voltage for both samples was smaller than 5–6 V, though it
depended on the layer thickness. When the voltage increased to 8.5 V, the luminescence intensity
for sample I saturated, though the current did not. For compound II, we observed no saturation
when the voltage changed within these limits. The saturation is most likely caused by the
recrystallization process observed for the examined compounds and unperceptible by the naked
eye. The recrystallization changing the film morphology was observed even at room temperature
together with the absorption and fluorescence spectra. In the process of OLED operation, the
temperature increased, and the recrystallization was amplified. The luminescence brightness was
sufficiently high. The electroluminescence spectra for both compounds were similar. They were
observed in the same wavelength range as the photoluminescence spectra; however, their
maxima were significantly shifted toward longer wavelengths. From the short-wavelength side
of this spectrum, an additional shoulder was observed caused most likely by the contribution of
polyvinylcarbazole luminescence. High currents running through the OLED demonstrate good
electron transport properties of the given compounds.
65
MAGNETIC FIELD EFFECT ON THE POLYARYLENEPHTHALIDES
ELECTROLUMINESCENCE
A.A. Kovalev1, V.A. Antipin2, A.N. Lachinov1, S.N. Salazkin3, V.P. Kazakov2
1 - Institute of Physics of Molecules and Crystals URC RAS, Ufa, Russia
2 - Institute of Organic Chemistry URC RAS, Ufa, Russia
3 - Institute of Elementoorganic Chemistry RAS, Moscow, Russia
lachinov@anrb.ru
Electroluminescence (EL) is a recombination process. Its probability depends on different
quantum parameters of a multilayer structure. One of these parameters is spin of the relaxing
electron. Spin orientation of the injected electron can be changed by the external magnetic field.
In this work EL’s parameters subject to the influence of the external magnetic field were
investigated. The results of this experiment are presented.
The EL was measured in the Al/polymer/ITO multilayer structure (ITO is mixture of indium
oxide and tin oxide). The non-conjugated polymer was used from the polyarylenephthalide class,
namely, statistical copolymer polyaryleneetherketones (co-PAEK). Polymer film (560 nm pf
thickness) was deposited on the surface of the ITO layer. Used solution for polymer was
cyclohexanone. Aluminium electrode was deposited on the polymer film by vacuum evaporated
technique. Measurement were carried out at normal atmosphere and room temperature.
Early it was shown that co-PAEK demonstrated satisfactory EL with spectrum in visible region.
6
Magnet
field Offполя
Без магнитного
Electroluminescence,
arb.un
Интенсивность (отн.
ед.)
5
4
В магнитном поле
Magnet
field On
3
2
1
0
200
300
400
500
600
700
800
900
Длина волныnm
(нм)
Wavelength,
Fig. 1. EL spectrums outside (solid line) and inside (dotted line) of the magnetic field.
The influence of the magnetic field on the EL spectrums is shown in fig. 1. Spectral shape
changes inessential. But the EL intensity considerably reduces in the magnetic field presence.
Mechanism of the observed effect and features of the magnetic field influence are discussed in
the report.
66
EXIPLEX ELECTROLUMINESCENCE SPECTRA
IN THE ORGANIC LIGHT-EMITTING DIODES
BASED ON SULPHANYLAMINO ZINC COMPLEXES
S.S. Krasnikova, M.G. Kaplunov, I.K. Yakushchenko
Institute of Problems of Chemical Physics RAS, Russia
skras@cat.icp.ac.ru
It is well known that the electroluminescence (EL) spectra of the most of organic materials are
similar to their photoluminescence (PL) spectra. This is due to the fact that the same energy
levels are involved in the EL and PL processes. For some of our devices an opposite situation is
observed: the EL spectra significantly differ from the PL spectra of the organic components. The
shape of the EL spectra depends on the composition of the hole-transporting layer.
We have measured the EL spectra of the organic light-emitting diodes based on the new zinc
complexes with sulpanylamino-substituted quinolines and 2-phenyl-benzazoles [1]. The EL was
observed for the layered structures containing the transparent anode of indium-tin oxide (ITO),
organic hole-transporting layer, luminescent layer of one of the studied complexes and the
metallic cathode.
In the EL spectra of the devices, the component band with the maximum at about 450 nm is
observed which may be attributed to the electronic transitions intrinsic for the zinc complex. This
component coincides with the PL spectrum of the sample. Besides this intrinsic band, the
additional wide band is observed in the region of 500-650 nm. While PL is excited in the bulk of
the film, EL arises at the interface of the hole-transporting and the electron-transporting layers.
The additional long-waved EL band may arise due to an intramolecular interaction at the
interface probably as a consequence of the formation of exiplex between molecules of holetransporting and luminescent materials. The relation of intensities of the intrinsic and exiplex
bands depends on the material of the hole-transporting layer.
Due to large widths of the EL spectra from blue to red spectral region, the light from some
devices is nearly white. The CIE color coordinates of one of the devices are x=0.30, y=0.34
which is close to pure white (x=0.33, y=0.33).
1. M. G. Kaplunov, I. K. Yakushchenko, S. S. Krasnikova, A. P. Pivovarov. Electroluminescent
Devices Based on Novel Zinc Complexes of Sulphonylamino Substituted Heterocycles
Mol. Cryst. Liq. Cryst., Vol. 497, pp. 211–217, 2008
67
INFLUENCE OF ETHANOL VAPORS ON SPECTRAL BEHAVIOR
OF NILE RED IN ORGANIC-SILICATE MATRIX
D.I. Lupikov, T.G. Movchan
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
movchan@phyche.ac.ru
One of the prospective ways of sensor technologies development is making of optical chemical
sensors. Through optical characteristics change of sensor material, composed of moleculeindicator, situated on solid matrix, it can be judged about the analyte presence. Fluorescence is
more sensitive and informative enough optical characteristic. Organic polymers, providing high
fluorescence intensity and preventing the effects of dye protonation, which influence decreases
dye emissivity, are often used in chemical sensor structures. In paper [1] strong hydrogen bond
polymer was used for matrix preparation of fluorescent sensor. The effect of dye protonation in
polymer matrix led to increase of fluorescence intensity in analyte vapors. Pore structure in
combination with optical clarity and mechanical strength makes silicate sol-gel matrix in
aggregate with introduced at room temperature organic modifiers an attractive material for wide
application in photonics, including as optical sensor [2].
Protonation effects in organic-silicate sol-gel systems, produced with silanol groups Si–OH of
quartz glass and/or alcohol groups can cause increase of fluorescence intensity in analyte vapors,
as in the case of acidic polymer [1]. Investigation of hybrid sol-gel matrix, prepared by synthesis
of tetraethoxysilane (TEOS) and 3-glycidoxypropyltrimethoxysilane (GLYMO) with subsequent
introduction of Nile Red (NR), concerning the effect of ethyl alcohol vapors by fluorescence
analysis was the purpose of this work.
Tenfold increase of dye fluorescence intensity was found out in the experiments with samples as
films of 40TEOS:60GLYMO composition by way of response to ethanol vapors. Fluorescence
intensity of dye decreased after film heat treatment, taken on a value similar to original state.
The effect of fluorescence “building-up” of NR, situated on solid matrix, under ethyl alcohol
vapors exposure can be explained by change of dye molecules environment. Apparently,
sorption of ethanol vapors was carried out in competition of dye NR and ethanol to interaction
with sides of hybrid matrix. As a result of dye displacement from hydrogen bond matrix sites its
local environment and so fluorescent properties changed. Low-polarity environment, in which
dye has configuration with high fluorescent properties, was created by glycidoxypropyl groups
of GLYMO [3]. As a result of heat treatment removal of alcohol vapors occurred, dye molecules
reverted to original environment that led to decrease of fluorescence intensity.
Literature.
[1] Levitsky I., Krivosclykov S.G., Grate J. W. //Anal. Chem. 2001. B. 73. P. 3441
[2] Schmidt H., Scholze H. and Tünker G. // J. Non-Crystall. Solids. 1986. V. 80. P. 557
[3] Ferrer M.L., del Monte F. // J. Phys. Chem. B. 2005. V. 109. P. 80
68
EFFICIENT MULTILAYER ELECTROLUMINESCENT ORGANIC
STRUCTURES BASED ON IRIDIUM(III) COMPLEX
D.A. Lypenko, A.V. Dmitriev, E.I. Maltsev, A.V. Vannikov
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, RAS, Moscow, Russia
lypenko@rambler.ru
In phosphorescent compounds, strong spin-orbit coupling leads to efficient intersystem crossing
of the singlet excited states to the triplet manifold, and also mixes the singlet and triplet excited
states, removing the spin-forbidden nature of the radiation transition of the triplet state to the
ground state. Various kinds of phosphorescent organic materials and many electroluminescent
OLED structures based on these dyes have been tested. Here we report a highly efficient
multilayer electroluminescent (EL) organic structure using the iridium(III) complex as a dopant
in the emitting layer. Typical developed OLED structure with six functional organic layers
(Fig.1) and its emission band (Fig.2) are given below.
80 nm Al
1
5 nm Sm/Al
15 nm BPhen
6 nm BCP
25 nm Ir complex:TAZ
EL, a.u.
1 nm LiF
0.5
10 nm NPD
40 nm 2-TNATA
5 nm CuPc
ITO
Glass substrate
Fig.1
0
350
450
550
650
750
Wavelength, nm
Fig.2
Device configuration we have developed was as follows ITO/Cooper (II) phthalocyanine/4,4′,4″tris[2-naphthyl(phenyl)amino]triphenylamine/N,N’-diphenyl-N-N’bis(1-naphthylphenyl)-1,1’biphenyl-4,4’-diamine/ bis(2-phenylpyridine) iridium(III) acetylacetonate : 3-(Biphenyl-4-yl)-4phenyl-5-(4-tert- butylphenyl)-1,2,4- triazole /2,9-dimethyl-4,7diphenyl-1,10-phenanthroline/
4,7-Diphenyl-1,10-phenanthroline/ LiF/ Sm(5%):Al/ Al.
In conclusion, high efficiency (23 lm/W) and low turn-on voltage (3,5 V) using the complex as a
phosphorescent dopant in the emitting layer have been demonstrated.
69
DYNAMICS OF ABSORPTION AND LUMINESCENCE
OF CdSe/ZnS QUANTUM DOTS IN THE PROCESS
OF AGGREGATION IN HYDROPHOBIC SOLUTIONS
V.G. Maslov, V.E. Adrianov, A.O. Orlova, A.V. Baranov, A.V. Fedorov
St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
maslov04@bk.ru
Currently, one of the most important and rapidly developing areas of nanotechnology is the
creation of ordered structures of nanoparticles, such as colloidal quantum dots (QDs). Depending
on the number and composition of nanoparticles these structures could have the remarkable
properties, in particular, the ability to accumulate the absorbed radiation and transform it, e.g. to
change the parameters of QD luminescence spectra. In this regard, determining the conditions of
spontaneous QD aggregate formation with such properties in solution is of special interest.
In this work the dynamics of spontaneous aggregation of CdSe/ZnS QDs capped with
Trioctylphosphine oxide (TOPO) with deficiency of TOPO on the QD surface has been
investigated in hexane, carbon tetrachloride, and chloroform at low QD concentrations (about
5·10-7М). It was shown that the dynamics of spontaneous QD aggregate formation and their
optical properties are primarily determined by the choice of solvent. So, in hexane the fast
spontaneous aggregation accompanied with the significant decrease of luminescence of solution
with the characteristic time of about 2.5 hours and subsequent precipitation of QDs aggregates
were observed. The addition into the solvent of the TOPO access with the concentration of 3·10-4
prevents the spontaneous aggregation of nanocrystals and ensures the stability of the optical
properties of the QD solutions during tens of hours.
Completely different picture was observed in the TOPO deficient QDs in chloroform. It should
be noted that this solvent, unlike hexane, could be coordinated on the surface of QD, replacing
TOPO molecules. It was found that QDs in chloroform are initially in aggregated state. This is
reflected in the significantly lower luminescence quantum yield (by two orders of value lower
than in hexane), and in larger halfwidth of QD luminescence band (FWHM is 32-35 nm
compared to 26 nm in hexane). Investigation of the evolution of absorption and luminescence
spectra of the QD solution showed that the rapid precipitation of QD aggregates from the
solution took place. At the same time, the remaining in the solution QD aggregates underwent
significant changes. This was evidenced by the broadening of absorption spectrum characteristic
for larger aggregates as well as by some abnormal changes in luminescence spectrum of the
solutions: an increase of luminescence intensity and the hypsochromic shift of luminescence
band. Such an evolution of the spectra may be an indication of the penetration of solvent
molecules inside the QD aggregates, leading to a gradual loosening and disaggregation. This
suggests that in few dozen hours the formation of new type QD aggregates in chloroform takes
place with hypsochromically shifted luminescence band (520 nm compared with 530 nm in
hexane) and with QD luminescence quantum yield, comparable with the quantum yield in
hexane. The addition of TOPO in chloroform does not lead to stabilization of the solution.
In carbon tetrachloride the QD solutions were stable within tens of hours. However some longtime changes of luminescence and absorption properties took place: considerable hypsochromic
shift of both absorption and luminescence bands. These changes can be explained by the partial
substitution of TOPO by the solvent molecules which like the chloroform molecules can
coordinate to the QD surface.
70
QUENCHING OF ELECTRONICALLY EXCITED CARBAZOLE
BY A STABLE IMIDAZOLIDINE RADICAL
A.G. Matveeva1, D.V. Stass1, V.V. Korolev1, V.F. Plyusnin1, V.A. Reznikov2
1 - Institute of Chemical Kinetics and Combustion, Novosibirsk State University, Russia
2 - Novosibirsk Institut of Organic Chemistry, Novosibirsk State University, Russia
matveeva@kinetics.nsc.ru
The processes of intermolecular quenching of excited states of aromatic hydrocarbons by various
free stable radicals are one of the rather well developed branches of molecular photochemistry.
Much interest today is directed towards quenching in linked systems, where the quencher and the
luminophore are parts of the same molecule.
It has been demonstrated that in the studied linked systems the quenching proceeds via the
mechanism of exchange-induced relaxation of the local excited state of the luminophore, while
in free systems the entire range of classical quenching mechanisms can be observed.
In this work as a part of the program on creating model radiation-induced three spin systems we
synthesized a precursor system “carbazole CBZ – imidazolidine nitroxyl radical R•”, studied its
photophysical properties, and compared it to free CBZ and R• in solution.
N
Фт (CBZ) = 0.36
Фs (CBZ) = 0.38
Фs,т (CBZ-R ) = ?
N
N
O
For the linked system CBZ-R• the relative decrease of quantum yield and fluorescence lifetime
of the local singlet-excited state was estimated to by about 103. No locally excited triplet state of
the carbazole moiety was registered at times 50 ns and longer. For the chemically non-bound
CBZ and R• the rate constants of intermolecular quenching of singlet and triplet excited states of
carbazole in acetonitrile were found to be (1.4 ± 0.1)×1010 M-1sec-1 and (1.5±0.2)×109 M-1sec-1,
respectively. Based on the results of our experiments we suggest exchange-induced energy
transfer and exchange-induced acceleration of local relaxation as the most plausible quenching
mechanisms. We shall also discuss the processes of Forster energy transfer, electron transfer, and
accelerated intersystem crossing for this system.
Work supported by RFBR (projects 08-03-00313, 07-02-91016-AF), INTAS (project 0510000008-80) and the Program of the Division for Chemistry and Material Science RAS for
2009 (project 5.1.6.).
71
OPTICAL FORMATION OF GRADED-INDEX WAVEGUIDE
STRUCTURES IN PHOTOPOLYMERIZABLE COMPOSITES
S.N. Mensov, Yu.V. Polushtaytsev
G.A. Rasuvayev Institute of Organometallic Chemistry RAS, Nizhny Novgorod, Russia
mensov@iomc.ras.ru
Nowadays, photopolymerization methods are commonly used to produce optically homogeneous
materials and they allow to shape the surface of an optical element at one time. Polyfunctional
monomers (as a rule, di(meth)acrylates) are employed for this processes. Photopolymerization of
them results in polymer formation with nano-sized reticular structure which doesn’t scatter
optical radiation. However, graded-index materials with preset distribution of the refraction
parameter are more effective for optics. Refraction parameter profile adjusting makes it possible
to improve technical features of waveguide structures considerably and to provide optical flow
separation and joining. Polymer net structure controlling allow to create stable graded-index
optical materials by light directly if additional non-polymerizable compounds (NC) differing in
refraction parameter are used in the mixture of photopolymerizable composite (PPC). Among the
neutral compounds are molecular and ionic solvents. The process of composite compounds
redistribution during polymerization depends on the monomer conversion rate, determined by
actinic radiation intensity. Realization of nonlinear wave processes in such mediums gives an
opportunity for optical synthesis of the elements for fiber optics [1], formed directly by light but
proof against actinic radiation. Low-energy mechanisms of interaction with irradiation are
typical for PPC. However, realization of nonlinear wave processes require low-absorbing
composite with spectral sensitivity out of the monomer absorption band. O-quinones meet this
requirements and they initiate photopolymerization of oligomers upon the acting of the visible
radiation.
In this paper we consider nonlinear wave processes of waveguide structures optical formation in
transparent PPC with NC. A diffusion model for the process of the PPC compounds
redistribution during the photopolymerization by inhomogeneous irradiation has been
formulated. Conditions of stable polymeric waveguide formation by laser irradiation with
essential diffractive divergence have been determined, in particular, for the radiation propagating
from the ends of standard quartz fibers. Stable
polymeric waveguide structures compatible with
standard quartz fibers have been synthesized in the
PPC based on the mixture of methanol and oligomer
OCM-2 with quinone photoinitiating complex by the
low-energy laser irradiation (the power was less than Fig.1 – Polymeric channel synthesized by light
between the fibers CS-980 and SMF-28.
10 mW).
This work was supported by RFBR (grant №№ 08-03-12090, 08-03-97055 and
09-03-00668.
[1] Mensov S.N., Polushtaytsev Yu.V. Optical Connecting of Fibers by Laser Beams
Propagating From the Fibers Edges // Advances in Optical Technologies, 2008, vol.2008,
Article ID 719632, doi:10.1155/2008/719632.
72
NOVEL PHOTOCHROMIC SPIROPYRAN CATIONS WITH
A PYRIDINIUM MOIETY IN THE ALIPHATIC SIDE CHAIN
A.V. Metelitsa1, S.O. Besugliy2, N.A. Voloshin2, E.V. Soloveva1, V.I. Minkin1
1 - Institute of Physical and Organic Chemistry, Southern Federal University,
Rostov-on-Don, Russia
2 - Southern SC RAS, Rostov-on-Don, Russia
met@ipoc.rsu.ru
+
-
+
-
Salts of spiropyrans (SP X ) and spirooxazines (SO X ) hold promise for the development of hybrid
polyfunctional materials, combining photochromic and magnetic properties in a single crystal lattice,
in which the spiropyran or spirooxazine cations have photochromic properties. In a continuation of
these studies, a series of cationic spiropyrans (SPP) 1-4 containing a pyridinium fragment in the
aliphatic side chain have been synthesized.
1
R
Me
Me
1
hν, ∆
R2
N O
Me
N
+
X
_
hν, ∆
R
R2
Me
Me
+
N
O
Me
А
_
N X
+
_
В
1 R1 = Cl, R2 = NO2, X = Cl; 2 R1 = OMe, R2 = NO2, X = Cl;
3 R1 = R2 = H, X = Br; 4 R1 = Cl, R2 = H, X = Br
The electronic absorption spectra of the cyclic isomers of spiropyrans 1-4 in acetonitrile show long-wavelength
bands at 290-345 nm with molar extinction coefficients at the maxima 3480-8180 mol
1
-1
and stronger
bands with maxima at 245-259 nm and
·dm3·cm corresponding to an S0→S1 transition
-1
-1
molar extinction coefficient 16210-24190 mol ·dm3·cm for the S0→S2 transition.
Irradiation of solutions of spiropyrans 1-4 in acetonitrile by UV light at the absorption bands of the
cyclic isomers leads to coloration related to clevage of a C–O bond and subsequent cis-trans
isomerization and the formation of a colored metastable product B. The maxima of the longwavelength bands of the acyclic merocyanine isomers B of spiropyrans 1-4 are in the range of 540586 nm. The merocyanine forms of SPP 1 and 2 demonstrate fluorescence at 293 K. The
fluorescence band maxima are in the range of 618-625 nm and the fluorescence excitation bands are
in good agreement with the long-wavelength absorption bands of merocyanine forms B.
Thermal relaxation processes В→А are observed after the termination of UV-irradiation. Generally,
the introduction of a quaternized pyridine fragment into the benzopyran part of the spiropyran
molecule leads to a decrease in the rate of the thermal recyclization by three orders of magnitude.
The photochemical channel for В→А recyclization was found under the excitation of the
merocyanine forms of compound 1 and 2 to both the S1 and S2. By contrast, upon irradiation in the
long-wavelength absorption bands of the merocyanine isomers of SPP 3 and 4 an increase in the rate
of bleaching for their pre-colored solutions could not be detected against the background of the
thermal relaxation.
This work was financially supported by Russian Foundation for Basic Research (Project No. 09-0300813) and by the Presidium of the Russian Academy of Sciences (Development of Methods for the
Preparation of Chemical Products and Development of New Materials, Program No. 18).
73
THEORETICAL STUDY OF ADSORPTION OF AN ACRIDINE DYE
AND SIMPLE MOLECULES ON A SILICA SURFACE
R.F. Minibaev1, N.A. Zhuravlev2, A.A. Bagaturyants1, M.V. Alfimov1
1 - Photochemistry Center RAS, Russia
2 - Moscow Engineering Physics Institute, Russia
minibaev@gmail.com
The study of the interaction of organic dyes with an inorganic substrate is an extremely
important problem in modern organic nanophotonics. In particular, this problem arises in the
development of new nanostructured materials for optical chemical sensors that can detect the
presence of small amounts of impurities in the gas phase by the change in the spectral properties
of the sensing material. The main functional element of such a material is an organic dye
molecule adsorbed on a substrate. Silica nanoparticles are a common substrate for the
hierarchical construction of nanostructured materials for optical chemical sensors. In this case,
studying the adsorption of possible analytes and organic dyes on the silica surface can provide
useful information about the structure and properties of the sensing material.
There are few papers in which the interaction of organic molecules with the silica surface has
been studied theoretically [1, 2]; however, no systematical theoretical investigation of the
interaction of various molecules and, in particular, dye molecules with the silica surface has been
published so far.
In this work, the adsorption of a number of simple molecules and acridine (considered as a
model of an acridine dye) is studied theoretically. The model of silica was constructed based on a
model of quasi-amorphous silicon oxide the structure of which was obtained by classical
molecular dynamics simulation. The silica structure was amorphized by heating at high
temperature followed by cooling.
Water, ammonia, acetone, and ethanol molecules were adsorbed on the obtained amorphized
surface. The acridine molecule was considered as a model for an acridine dye molecule. The
calculations of the adsorption of molecules were performed using the periodic slab
approximation.
Calculations were performed using density functional theory (DFT) with a generalized gradient
approximation (GGA) for the exchange-correlation potential. The most favorable adsorption
positions on the silica surface were found. The structures of the adsorption complexes were
calculated, and the adsorption energies of the molecules considered in this work on the silica
surface were found.
The electronic structure calculations of bulk alpha-quartz, quasi-amorphous silica, and silica
surfaces revealed changes in the electronic structure due to the adsorption of molecules.
1. Marco Nonella, Stefan Seeger // ChemPhysChem, vol. 9, pp. 414–421 (2008).
2. Albert Rimola, Mariona Sodupe, and Piero Ugliengo, J. Phys. Chem. C, 113, 5741–5750
(2009)
74
SPECTRAL BEHAVIOUR OF NILE RED
IN ORGANIC-SILICATE SOL-GEL MATRIСES
T.G. Movchan1, D.I. Lupikov1, T.V. Khamova2, O.A. Shilova2
1 – A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
2 – I.V. Grebenshchikov Institute of Silicate Chemistry RAS, St.Petersburg, Russia
Movchan@phyche.ac.ru
Last years interest to the sol-gel derived hybrid organic-inorganic materials has increased. The
reactions of hydrolysis and polyfunctional condensation of silicon alkoxides are the base for solgel processing and allow to include in oxide or hybrid matrixes a wide number of organic and
inorganic additives, which provide special ordered physical-chemical properties to synthesized
materials optical ones.
However molecule of some dyes does not display fluorescent properties in the protonized
mediums created by silanol groups which are present in sol-gel systems on the basis of alkoxy
silanes [1]. The revealed feature of epoxy groups in 3-glycidiloxypropyltrimetoxysilane
(GLYMO) to reduce effect of protoning owing to formation by these groups of a protective
barrier [1] has allowed to assume about an opportunity of use for these purposes of other epoxy
combination.
The present paper is devoted to research of influence of a weight ratio of the basic components
of a hybrid matrix (E and S) as well as solvents remaining in its pores on spectral behavior of
dye Nile Red (NR).
Hybrid organic-inorganic materials (gels, xerogels and glasses) based on sol-gel systems
obtained by copolymerization ingredients of silicate (S) - of tetraethoxysilane (TEOS) and of
organic (E): a) 3-glycidoxypropyltrimethoxysilane (GLYMO); b) mixture (50/50) of epoxy
resins (DEG-1 and ED-20) with the different proportions (rE/S): 0/100; 20/80; 30/70; 40/60;
50/50; 60/40; 70/30. Concentrations of NR in sols are 2.2 · 10-7 moles. Spectrums of
fluorescence have been obtained using spectrometer Perkin-Elmer LS’-55.
Influence of a ratio of inorganic and organic components of a hybrid matrix in which are
distributed nanosized inclusions of dye on spectral behavior of NR (shift of a wave of fluorescent
radiation, emission intensity) is revealed. Two maxima on spectrums of radiation occur. It is
supposed that occurrence of two peaks of emission for hybrid materials is caused by formation of
structure interpenetrating inorganic (S) and organic (E) networks, and each network has the
specific parameters of radiation. Influence of solvents on behavior of NR in mediums of various
polarities is considered. At reduction of the contents of solvents in poorly polar medium the
spectrum of emission was moved aside shorter wavelengths (dark blue displacement) and, on the
contrary, in polar medium its removal resulted to displacement of an emission spectrum in the
long-wavelength side (red shift).
The analysis of data of IR-spectroscopy has shown that not all epoxy groups become convertible
in proton alcoholic groups. Owing to this a diminution of polarity of medium near to NR occurs.
Literature.
[1]. James W. Gilliland, Kazushige Yokojama,and Wai tak Yip. // J. Phys. Chem. B. 2005. V.
109. P.4816-4823.
75
NEW PHOTOCHROMIC ASYMMETRIC BISPIROPYRAN
OF THE 2,3-DIHYDRO-4-OXO-NAPHTO[2,1-E]OXAZINE SERIE
E.L. Mukhanov1, B.S. Lukyanov1, I.V. Dorogan1, S.O. Besuglui2,
Yu.S. Alexeenko2, O.N. Ryashin1, V.V. Tkachev3
1 - Institute of Physical and Organic Chemistry, South Federal University,
Rostov-on-Don, Russia
2 - Southern SC RAS, Rostov-on-Don, Russia
3 - Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
lab811@ipoc.rsu.ru
Bispiropyrans – compounds contatining two spirocyclic fragments in the structure are objects of
special interest for researchers.
We have synthesized new asymmetric bispiropyran 1 containing two different spirocenters and
consequently two asymmetrical carbon atoms.
H3C
O N
H3C
O
N
O
O
H3C CH3
1
Picture 1. Structure of bispiropyran 1 detected by X-Ray analysis
Data of the quantum-chemical computations proved that obtaining of several isomers takes place
as a result of opening of both pyran cycles in the molecule 1. This result is the first affirmed
example of the simultaneous break of two Cspiro – O bonds for bispiropyranic systems.
0,06
0,030
0,05
0,025
продукт накоплен ранее
0,07
D 0,035
abs
0,04
0,020
0,03
0,015
0,02
0,010
0,01
0,005
0,00
0,000
-0,01
500
600
700
800
λ, нм
Picture 2. Absorption spectra of the bispiropyran 1
toluene solution at t = 20 °С
irr Σ
irr 313
irr 436
dark
-20
400
λ 613 nm
λ 507 nm
dark
0
20
40
60
80
100
120
140
160
180
200
time / s
Picture 3. Changes of the absorbance intensity at 613 nm
and 507 nm on the different experiment stages for the
bispiropyran 1 toluene solution
This work was financial supported by the program “Development of the scientific potential of
the high school” (RNP 2.2.1.1.2348), CRDF and the Ministry of Education and Science of
Russian Federation in the frame of Russian-American program “Basic research and high
education” (BRHE) (RNP 2.2.2.2.3915, RNP2.2.2.3.16011, BP3C04, BP4M04), Grant of The
President of Russian Federation NSh-363.2008.3. and Russian Foundation for Basic Research
(grants 07-03-00234-a, 08-03-90029-Bel).
76
COPOLYMERS BASED ON CYCLOPENTADITHIOPHENE
FOR ORGANIC PHOTOVOLTAICS
E.N. Myshkovskaya1, S.A. Ponomarenko1, P.A. Troshin2,
S.D. Susarova2, S.D. Babenko3, N.M. Surin1, A.M. Muzafarov1
1 - Institute of Synthetic Polymeric Materials RAS, Moscow, Russia
2 - Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
3 - Branch Institute of Energy Problems of Chemical Physics RAS, Chernogolovka, Russia
mafox@inbox.ru
In recent years organic semiconducting polymers are the subject of intensive research because of
high potential of their application in new generations of optoelectronic devices such as
photovoltaic cells, light-emitting diodes, thin-layer transistors, etc. Among these polymers of
particular interest are copolymers based on cyclopentadithiophene and its derivatives due to high
solubility, low band gap and good transport properties of such materials. This paper presents
synthesis of new copolymers of 4,4-dialkylcyclopenta[2,1-b:3,4b’]dithiophene with 9,9dialkylfluorene (1) and 4,4-dialkylcyclopenta[2,1-b:3,4b’]dithiophene with spiro[4H-cyclopenta
[2,1-b:3,4b’]dithiophene-4,2'-[1,3]dioxolane (2) (Fig. 1). For their preparation, we have
improved some methods of synthesis of the monomeric precursors, as well as suggested a new
synthetic way for the monomer based on 1,3-dioxolane derivative of the cyclopentadithiophene.
Purity and molecular structure of the monomers and precursors for their obtaining was proved by
NMR, mass spectroscopy and elemental analysis. Copolymers were prepared by the Suzuki
reaction from the corresponding dihalogen and diorganoboron derivatives.
R
O
R
*
n
S
*
S
R
1
R
*
O
S
S
S
R
S
*
n
R
2
R = -Oct, EtHex
Fig.1. Structural formulas of the copolymers obtained
Study of the optical properties of the copolymers obtained showed that copolymers 1 possess the
strong absorption of light in the region from 400 to 500 nm, showing significant
photoluminescence in the solution (quantum yield of 34% - 47%). The absorption of copolymers
2 is shifted to the red region on 60-70 nm as compared to copolymers 1, but they have rather
weak luminescence. Measurement of the transport properties of diodes, prepared from the
copolymers obtained, showed the hole mobility, reaching 10-3 см2/V.s и 10-4 см2/V.s for
copolymers 1 and 2, respectively. Efficiency of the photovoltaic cells made on the basis of the
nanocomposites of the copolymers with the fullerene derivative C60 (PCBM) was 0.36 - 0.53%.
This work was supported by the Federal Agency for Science and Innovations (State Contract №
02.513.11.3382).
77
MEAN FORCE POTENTIALS FOR ION PAIRS
IN A BINARY SOLVENT MIXTURE
A.V. Odinokov1, M.V. Basilevsky1, E.A. Nikitina2, N.Kh. Petrov1, M.V. Alfimov1
1 - Photochemistry Center RAS, Moscow, Russia
2 - Institute of Applied Mechanics RAS, Moscow, Russia
ale.odinokov@gmail.com
Mean force potentials (MFP) are calculated for two model symmetric ion pairs in the
benzene/dimethylsulfoxide (DMSO) mixtures. The electrostatic part of the interaction free
energy was found in MD simulations, which accounted for a separate treatment of fast electronic
and slow nuclear components of the solvent polarization in terms of the recently developed
methodology. Alternative computations of the electrostatic free energy in terms of the continuum
solvent model are performed and compared with the molecular level simulation. The
composition of the solvent mixture is determined as the average molecular fraction of DMSO,
denoted as x. Change of x in the range 0<x<0.1 generates the variation of the MFP. The
potentials treated as a function of inter-ion separation vary from deep wells, corresponding to
contact ion pairs (x=0, pure benzene) to simple-shaped monotonously changing repulsive curves
with flat minima; they are determined asymptotically by the dielectrically screened electrostatic
interaction (x>0.5). The latter state of the solution system is associated with solvent-separated
ion pairs. Intermediate composition range (x=0.1-0.2) is characterized by strong fluctuations of
MFPs caused by the fluctuations in the composition of the ion pair solvation shell.
The present work was performed with the financial support of RFBR grant 07-03-00479-a
78
STUDY OF A POLYMER MATRIX INFLUENCE ON PHOTOCHROMISM
OF SPIROPIRANES, INSERTED BY DIFFUSION FROM SOLUTIONS
V.A. Optov1, A.O. Ait2, V.A. Barachevsky2, A.A. Berlin1, O.Yu. Sabsai1
1 - N.N. Semenov Institute of Chemical Physics RAS, Moscow, Russia
2 - Photochemistry Center RAS, Moscow, Russia
ait@photonics.ru
Possibilities of obtaining the photochromic polymer composites by a method of diffusion
insertion of photochromic molecules in different polymer matrices (low density polyethylene,
polypropylene, polyurethane, polycarbonate, copolymers of ethylene with norbornene) were
studied. As a model photochromic compound there was used a nitrosubstuted spirobensopyrane
1`,3`-dihydro-1`,3`,3`- trimethyl-6-nitro-8-methoxyspiro [2H-1-bensopyrane-2,2`-(2Н)-indole],
which possesses reversible photodissociation of –C-O bond and the following cis- , transisomerisation.
Comparative spectral-kinetic studies of the obtained samples were carried out, and there were
determined the constants of photocolouring and spontaneous decolouration, as well as
photodegradation. For the studied spiropyran there was made a quantitative evaluation of
coefficients of the diffusion into polymer matrices from organic solvents (iso-butanol, benzene)
and also quantitative evaluation was made for achieved concentrations of the spiropyran in a
polymer volume.
It was shown, that for all of the studied polymer samples there was observed a photochromic
effect. Depending on the polymer nature, substantially changes the kinetics of the composite
colouring at UV-irradiation and the following spontaneous decolouration.
79
FORMATION AND DISSOCIATION OF SEMICONDUCTOR QUANTUM
DOT / DYE MOLECULE COMPLEXES
A.O. Orlova, Yu.A. Toporova, V.G. Maslov, A.V. Fedorov, A.V. Baranov
St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
a_v_baranov@yahoo.com
Last ten years semiconductor nanocrystals or quantum dots (QDs) are widely used in sensory
systems for biological, medical and ecological applications [1]. It is expected that possibility to
manage QD luminescent parameters by simple change of their size together with high
photoluminescence QY and high photostability of QDs [2] can lead to step-by-step replacement
of traditional organic luminophores by QDs. Luminescent nanosensors sensitive to metal ions or
ions of hydrogen which luminescent response based on changes of efficiency of nonradiative
resonant energy transfer from photoexcited nanocrystal to some acceptor of energy are
intensively studied [3].
In present work formation of QD/azo dye complexes in different hydrophobic solvents due to
coordination bonding of molecules with metal ions of the nanocrystal shell has been studied by
means of absorption/luminescence methods. Hydrophobic core/shell CdSe/ZnS QDs were used
in the experiments while 1-(2-pirydilazo)-2-naphtol (PAN) which forms chelate complexes with
ions of different metals [4]. It was expected that in this case molecules are in direct contact with
QD surface that results in total quenching of luminescence of QD in QD/molecule complex. The
presented results are support our expectation. The QD/PAN complexes in toluene solution were
embedded in polymer film. It was found that when this film is placed in water containing Co or
Ni ions the QD luminescence appears with intensity proportional to concentration of ions in the
solution. The characteristic changes of absorption spectra of the films were simultaneously
observed, namely, disappearance of absorption bands of Zn/PAN complex and growth new
bands associated with complexes of azo dye with Co2+ or Ni2+. The data show that diffusion Co
or Ni ions from water solution to polymer film containing QD/PAN complexes results in
dissociation of these complexes followed by appearance of QD luminescence. It was concluded
that polymer films with embedded QD/PAN complexes can be considered as luminescence
nanosensor. Absence of sensor luminescence without ions shows principal possibility to reach
sensitivity allowing detection of single metal ion.
1. I.L. Medintz, H. Mattoussi, A.R. Clapp, Intl Journal of Nanomedicine, 3(2), p. 151 (2008).
2. А.В. Федоров, А.В. Баранов «Оптика квантовых точек». в сб. Оптика наноструктур.
Под ред. А.В. Федорова: СПб. «Недра», 2005 г. C. 181.
3. P. T. Snee, R. C. Somers, G. Nair, J. P. Zimmer, M. G. Bawendi, and D. G. Nocera. J. Am.
Chem. Soc. 128, p.13320 (2006).
4. Иванов В. М. Гетероциклические азотсодержащие азосоединения // М.: Наука. 1982. –
С. 270.
80
ATOMIC FORCE MICROSCOPY STUDY
OF J-AGGREGATE NANOSTRUCTURES
O.M. Perelygina1, V.V. Prokhorov2, D.A. Lypenko1,
E.I. Mal’tsev1, A.V. Vannikov1
1 - A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS
2 - M.M. Shemyakin & Yu.A. Ovchinnikov Institute of Bioorganic Chemistry RAS
dremeself@gmail.com
Molecular aggregates play an important role in molecular optoelectronic devices and thus have
attracted great attention in both fundamental and applied research on bridging the gap between
the physics of a single molecule and bulk molecular crystal. J-aggregates are specific molecular
assemblies. They are characterized by a very narrow and intense absorption and emission bands
as well as by coherent excitation phenomena. Proposed theoretical models, describing the
relationship between the optical properties and the molecular arrangement within the molecular
aggregates, show that the aggregate structure reflects its optoelectronic properties. Therefore,
direct experimental investigation of the morphology of aggregates is of particular importance.
Here we report recently obtained results on the observation of J-aggregate structures, based on
some cyanine dyes, e.g. a triethylammonium salt of 3,3’-di(γ-sulfopropyl)-5,5’-dichlorothiacyanine, located on mica surface and in the very thin (several nm thick) conducting polymer
layers. Some of these structures are shown in the micrographs below.
a
nm
4
2
0
b
2
2
0
1
1
2
1-1 1.05nm
2-2 2.09nm
1
1 µm
3 µm
Fig. 1. Topographical AFM images and cross-sectional profiles of ribbon-like J-aggregates on mica (a) and in a
polyaniline film (b).
Implications of the molecular alignment in the supramolecular aggregates include the existence
of structural units with highly ordered molecular structures. On the bases of the obtained AFM
microscopy data various supramolecular models of the studied J-aggregates are discussed.
This work was supported by The International Science and Technology Center (project
no. 3718). Authors are grateful to B.I. Shapiro for synthesizing of the cyanine dyes.
81
NEW EUIII AND TBIII HEXAFLUOROACETYLACETONATES
WITH BIDENTATE O-DONOR LIGANDS:
SYNTHESIS, STRUCTURE AND OPTICAL PROPERTIES
D.N. Pleshkov1, S.V. Eliseeva1, K.A. Lyssenko2,
L.S. Lepnev3, O.V. Kotova1, N.P. Kuzmina1
1 – M.V. Lomonosov Moscow State University, Moscow, Russia
2 - A.N. Nesmeyanov Institute of Organoelement Compounds RAS, Moscow, Russia
3 - Division of Optics, P.N. Lebedev Institute RAS, Moscow, Russia
dimas666-hell@mail.ru
For cleaver design of new functional materials it is necessary to establish correlation between
their composition, structure and properties. It is well known that the insertion of suitable neutral
ancillary ligands into the inner coordination sphere of coordination compounds is one of the
easiest ways to control and modify their functional properties (e.g. luminescence, thermal
stability, volatility etc.). The feasibility of this method on many different classes of complexes
was demonstrated.
Herein, new mixed-ligand lanthanide hexafluoroacetylacetonates [Ln(hfa)3(Q)] (Ln = EuIII, GdIII,
TbIII, LuIII) with bidentate O-donor ligands (Q): 1,4-diacetylbenzene (acbz), 1,4diacetoxybenzene (acetbz), 1,4-dimethyltherephtalate (dmtph) and 2,2-dipyridyl-N,N’-dioxide
(dipyox) were investigated. In spite that lanthanide β-diketonates are widely investigated, there is
no data about structure and functional properties of Ln(hfa)3 with neutral bridging bidentate Odonor ligands. Synthetic conditions were optimized to obtain pure complexes with general
composition [Ln(hfa)3(Q)]. The laser desorption/ionization mass spectra of [Eu(hfa)3(Q)] exhibit
mixed-ligand ions [Lnx(hfa)y(Q)z]+. Single crystal X-ray diffraction analysis shown that
[Eu(hfa)3(acbz)], [Gd(hfa)3(acbz)] and [Tb(hfa)3(acbz)] are isostructural and crystallize in
triclinic crystal system, while [Eu(hfa)3(dmtph)] in monoclinic one. For the first time the
bridging function of chosen bidentate O-donor ligands was successfully utilized for formation of
polymeric mixed-ligand lanthanide complexes, [Ln(hfa)3(acbz)]n and [Ln(hfa)3(dmtph)]n. In
order to estimate the role of mixed-ligand complexes formation on optical properties (i) the
triplet state energy levels of neutral ligands were determined from the photoluminescence spectra
of Lu(NO3)3(Q)⋅nH2O, and (ii) quantum yield values, lifetimes of the excited states (at 77 and
298 K) of [Ln(hfa)3(Q)] were compared with initial Ln(hfa)3⋅2H2O (Ln = EuIII, TbIII). The results
of thermal analysis in nitrogen atmosphere shown that [Ln(hfa)3(Q)] are stable up to ~170–
210°С. Electronic ionization mass-spectrometry together with vacuum sublimation and thermal
analysis experiments shown the possibility of congruent sublimation of [Ln(hfa)3(Q)] (Q =
acetbz, dmtph, dipyox). Thin films of these compounds were obtained and their morphology and
optical properties were investigated.
This work is supported through Russian Foundation for Basic Research (№09-03-00850a).
82
SYNTHESIS AND OPTICAL PROPERTIES
OF HIGHLY LUMINESCENT CdS QUANTUM DOTS
A.E. Raevskaya, G.Ya Grodzyuk, A.L. Stroyuk, S.Ya. Kuchmiy
L.V. Pysarzhevsky Institute of Physical Chemistry of Nat. Acad. Sci. of Ukraine, Kyiv, Ukraine
alraevskaya@ukr.net
Intensity, arb.u.
Semiconductor nanoparticles with quantum-size effects (quantum dots) are now widely used as
the luminescent labels in the research of biological objects and as emitting components of lightemitting devices (LEDs). Synthetic approaches to the water-soluble highly-luminescent quantum
dots, which are of special interest for the biophysical research, still remain at the stage of
development. At the same time, the LED technologies require the procedures of formation of the
highly-ordered layers of quantum dots to be developed. Probably the most advantageous among
these procedures with regard to the aqueous quantum dot colloids consists in the layer-by-layer
assembly using polyelectrolyte molecules, specifically, polyethyleneimine (PEI).
The report describes an attempt to address these two problems simultaneously, employing PEI
both as a stabilizer of the CdS nanoparticles in aqueous solutions and, in prospect, as an
assembling agent at the formation of the highly-ordered quantum dot films. Using this approach
the ultrasmall CdS particles were produced at 60-80 °С, displaying the absorption threshold
shifted by more than 120 nm to shorter wavelengths as compared to the absorption threshold of
the bulk CdS. The strong hyspochromic shift and development of the fine structure of absorption
band, visible as a trio of the distinct peaks at 357,
326 and 264 nm, allow to assess the synthesized
CdS nanoparticles as quantum dots experiencing
0,9
strong spatial confinement of the exciton. The
2
estimations done by the semiempirical model [1]
showed the CdS quantum dots being as small as
0,6
1.6 nm. The size dispersion, calculated from the
1
spectral width of the three peaks mentioned, does
not exceed 1.5%.
0,3
The quantum yield of photoluminescence (PL) of
the CdS quantum dots is as high as 15%, thus
0,0
closing to the highest values obtained for CdS
300
400
500
600
700
nanoparticles synthesized in octadecene at 300 °С
Wavelength λ, nm
(17%) [2]. It was found than the PEI-stabilized
The absorption (1) and PL (2) spectra of the
CdS quantum dots have remarkable stability
PEI-stabilized CdS quantum dots. The PL
toward aggregation up to the semiconductor
excitation wavelength is 320 nm.
concentration of 0.1-0.2 M, i.e. the CdS content
three orders of magnitude higher than the
aggregation stability limit for typical polymer-stabilized CdS colloids. There exists an optimal
component concentration range producing the quantum dots of the smallest size and size
dispersion. The special features of the PEI-stabilized CdS quantum dots produced in the optimal
conditions led to a conclusion about the formation of some "magic" CdS clusters having
remarkable thermal and aggregation stability. The structure of the "magic" cluster is probably
close to that of a well-known cluster Cd32S14(SC6H5)36 with the cadmium sulfide core size of 15
nm, which has very close spectral properties [1].
[1] Torimoto T., Kontani H., Shibutani Y., Kuwabata S., Sakata T., Mori H., Yoneyama H. J.
Phys. Chem. B 105 (2001) 6838.
[2] Sapra S., Mayilo S., Klar T.A., Rogach A.L., Feldmann J. Adv. Mater. 19 (2007) 569.
83
STARLIKE OLIGOTHIOPHENESILANES
FOR PHOTOVOLTAIC APPLICATIONS
E.A. Shumilkina1, S.A. Ponomarenko1, P.A. Troshin2,
E.A. Hakina2, N.M. Surin1, A.M. Muzafarov1
1 - ISPM RAS, Moscow, Russia
2 - IPCP RAS, Chernogolovka, Russia
memoza85@mail.ru
The possibility of regulation of photophysical characteristics of macromolecules plays an
important role in the creation of functional materials for organic electronics and photonics. One
of the drawbacks of linear π-conjugated polymer systems is anisotropy of the optical and
electrical properties, as a result of which strict control over the molecular orientation during the
production of different devices is required. Possible solution to this problem is the development
of branched and hyperbranched macromolecular systems with isotropic properties. A
prerequisite for this work was the successful application of starlike terthiophenesilanes in
organic photovoltaic devices described in the literature [1]. Previously we have prepared a
number of linear and starlike bithiophenesilanes with significant luminescence [2]. In this work
we synthesized a series of star oligothiophenesilanes with varying lengths of conjugated
oligothiophenes fragments (Fig. 1). Solubility of these compounds is provided both by threeR
dimensional structure of tetra-substituted silicon
compounds and terminal solubilizing n–hexyle or 2ethylhexyle groups R. Study of the optical properties of
S
the compounds obtained under transition from ter- to
quinquethiophenesilanes showed the expected red-shift of
the absorption maximum from 385 nm to 437 nm, as well
n
R
S
Si
as an increase of the luminescence quantum yield from R
n
n
S
8% to 21%. The complex study of the photovoltaic
properties of the composites prepared from the
S n=3-5
R= C6H13
compounds obtained and fullerene derivatives С60 and
или C8H17
С70 showed perspectivity for their usage in the solar cells.
The maximum efficiency of the photovoltaic cell
n
R
obtained have raised with increasing of the conjugation
length and reached 1.0% for the quater- and and 1.3% for
Fig. 1. The generalized chemical
the quinquethiophenesilane. In the presentation especially
formula starlike
the synthesis of this series of compounds, as well as their
oligothiophenesilanes.
optical, thermal and photovoltaic properties will be
considered.
This work was supported by RFBR (grant 07-03-01037), Federal Agency for Science and
Innovations (Contract No. 02.513.11.3382) and by the Presidium of the Russian Academy of
Sciences (Program No. 27).
Literature:
1. S. Roquet, R. de Bettignies, A. Cravio, J. Roncali, J. Mater. Chem. 2006, 16, 3040-3045.
2. Shumilkina E.A., Borshchev O.V., Ponomarenko S.A., Surin N.M., Pleshkova A.P.,
Muzafarov A.M. Mendeleev Commun., 2007, 17, 34-36.
84
SYNTHESIS AND PHOTOLUMINESCENT PROPERTIES
OF SOME LANTHANIDE COMPLEXES (LN = EU3+, GD3+, TB3+, LU3+)
WITH ORTHO-SUBSTITUTED PHOSPHORYLPHENOLS
S.V. Shuvaev1, O.V. Kotova1, L.S. Lepnev2,
N.P. Kuzmina3, V.E. Baulin4, A.Yu. Tsivadze4
1 - Department of Material Sciences, M.V. Lomonosov Moscow State University, Russia
2 - Division of Optics, P.N. Lebedev Institute RAS, Moscow, Russia
3 - Department of Chemistry, M.V. Lomonosov Moscow State University, Russia
4 - Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
sergeyshuvaev@gmail.com
Nowadays, coordination compounds of rare earth elements with organic ligands play an essential
role in development of new luminescent materials: OLED, sensors, bioimaging etc.
In this work the main consideration is given to coordination compounds of Eu3+, Gd3+, Tb3+ and
Lu3+ with ortho-substituted phosphorylphenol ligands
HL1 OH
O
(Fig. 1). The synthetic route of such ligands is well
established and opens wild possibilities for the
P
variation of their denticity, complexes formation
ability and physicochemical properties. However, in
spite of high potential interest, no information
concerning phosphorylphenolate complexes with
lanthanides has been found to date.
The crystal structure of HL1 has been determined for
2
HL
the first time and the intermolecular hydrogen bounds
OH
O
are the key characteristic of this crystal structure,
O
P
which is usual for organic acids. Thus, lanthanide
complexes were synthesized by an interaction of the
potassium salt of HL and corresponding lanthanide
O
nitrate according to the following scheme:
Ln(NO)3 ⋅ H 2O + 3 KL → LnL3 . The composition of
the complexes has been determined according to
HL3
OH
O
elemental and IR-spectroscopy as well as
MALDI/LDI, NMR and thermal analyses. All these
P
methods proved the formation of the expected
compounds.
The analysis of photoluminescence spectra (λex = 337
nm) of gadolinium and lutetium complexes at 77 and
298 K results in determination of the triplet state levels
for these ligands at ~23000 cm–1 and for such class of
Fig. 1. Structural formulas of
the ligands the effective photoluminescence
ortho-substituted
sensibilization is possible only for complexes contains
phosphorilephenoles (HL).
of terbium ion.
This work is supported through Russian Foundation for Basic Research (№09-03-00850a).
85
A NEW TECHNIQUE TO FABRICATE DIFFRACTIVE OPTICAL
ELEMENTS ON THE BASIS OF PERMOLECULAR STRUCTURES
V.S. Solovjev1, A.V. Volkov2, N.A. Rasshchepkina3
1 - A.N. Nesmeyanov Institute of Organoelement Compounds RAS
2 - Image Processing Systems Institute
3 - Samara Aerospace University
Solovjev@polly.phys.msu.ru
To design high-efficiency diffractive optical elements (DOEs) the calculation there of should be
conducted in the electromagnetic theory approximation. The calculations suggest that the
characteristic features of the DOEs are in the range from several wavelengths to one tenth of the
operating wavelength. In the optical range, the minimal wavelength is 0.4 µm. In this
connection, there is a need for a technique to fabricate arrayed periodic structures, capable of
producing the minimal DOE characteristic feature as small as 0.04 µm.
We propose a novel combined technique to fabricate the DOEs in a new recording medium
capable of building arrayed high-frequency periodic structures through self-organization. A
traditional lithographic technology makes it possible to control these structures. A siloxane
oligomer applied onto a substrate serves as the recording medium.
In this work, we report the formation of permolecular structures on the surface of variedthickness siloxane films exposed to a directed flow of IR light. For different siloxane polymers,
the width of the resulting permolecular structures formed in the 2µm-films is 5 µm. Similar
experiments are conducted for the film thickness in the range of 0.1 – 0.15 µm. For the thinner
films, the width of the permolecular structures was 0.4 – 0.6 µm. In this way, we show that the
transverse size and period of the permolecular structures can be governed by the film thickness.
The permolecular structures are formed on different substrates. Depending on the conditions,
different types of the permolecular structures are formed: globular, lamellar, and cylindrical.
We show that by preliminarily creating, through conventional lithographic techniques, a specific
relief configuration it is possible to form the permolecular structures of designed size, period,
and direction.
The new combined DOE fabrication technique includes:
• formation on the substrate – through the conventional lithography – of a specific
configuration that will determine the direction and length of the permolecular
structure;
• application of a thin siloxane film onto the substrate; and
• formation of the permolecular structure.
86
POLYMER/NANOCARBONS COMPOSITE MATERIALS
FOR PHOTONICS
N.G. Spitsina, A.S. Lobach, M.G. Kaplunov
Institute of Problems of Chemical Physics RAS, Chernogolovka
spitsina@icp.ac.ru
The discovery of a very efficient photoinduced electron transfer from conjugated polymer (CP)
to [60]fullerene opened up new aspects with potential applications of nanocarbons in fotonics,
non-linear optics, optoelectronics and organic photovoltaics (PV). The core of PV devices is the
interpenetrating biscontinuous donor/acceptor molecular network, where CP acting as a donor
(D) and nanocarbon materials (NCM) acting as an electron acceptor (A) [1].
A series of NCM has been synthesized: C60; azahomo[60]fullerenes and (4-6)
poly(amino)[60]fullerenes; [60]fullerene dimmers; single-walled carbon nanotubes. The
structure of the NCM was studied by cyclic voltammetry, 13C NMR-, UV-VIS-NIR-, FTIR-,
Raman spectroscopy [2-4]. Photoluminescence quenching experiments, current-voltage
measurements were performed on sandwich type cells based on CP [MEH-PPV, P3HT] and
CP/NCM blend films to investigate the charge transfer process. Preliminary results indicate that
NCM under investigations have a potential for use as electron acceptors in polymeric solar cells.
Series of microscopy methods TEM and AFM (tapping mode) has been used to investigate
CP/NCM blend film microstructure. The morphologies of NCM under investigation and C60
species in MEH-PPV matrix are sufficiently different. Thus, we seen that azahomo[60]fullerene
derivative formed linear extended structures (rod-like formations - thickness is approximately
100 nm and length of several micrometers), in contrast with C60 which formed a ball-shaped
aggregates with dimensions around 10 nm. Microstructure – properties correlation of the
CP/NCM blend film were discussed. Also, we discuss the way of increasing anisotropic
properties of the polymeric matrix by means of design of NCM and D-A self-organization
towards the desired nanomorphology of the composite film.
This work was supported by RFBR, Grant No. 08-03-01017.
[1] N.S. Sariciftci, L. Smilowitz, A.J. Heeger, F. Wudl. Science, 258 (1992) 1474.
[2] N.G. Spitsina, I.P. Romanova, A.A. Lobach, I.K. Yakuschenko, A.S. Lobach, M.G.
Kaplunov, I.V. Tolstov, M.M. Triebel, and E.L. Frankevich. Fullerenes, Nanotubes, and
Carbon Nanostructures, 14 (2006) 435-439.
[3] A.S. Lobach, I.S. Ryzhkina, N.G. Spitsina, E.D. Obraztsova. Phys.Stat.Sol. (b), 244 (2007)
4030-4034.
[4] N.G. Spitsina, M.V. Motyakin, И.O. Bashkin, K.P. Meletov. J.of Phys.: Cond. Mat., 14
(2002) 11089-11092.
87
DESIGNING FULLERENE/POLYMER BULK HETEROJUNCTION
SOLAR CELLS WITH ADVANCED ACTIVE LAYER MORPHOLOGIES
D.K. Susarova1, P.A. Troshin1, S.D. Babenko2,
R.N. Lyubovskaya1, V.F. Razumov1
1 - IPCP RAS
2 - Institute for Energy Problems of Chemical Physics RAS (Branch)
diana-susarova@yandex.ru
It was shown recently that an active layer morphology in organic solar cells can be controlled
using some additives that serve as co-solvents dissolving one component of the blend much
better than another.
Here we showed that addition of 5-10% (v/v) of 1,8-octanedithiol (ODT) to chloroform used as a
solvent for casting of the P3HT/PCBM blend films resulted in improved photovoltaic
performances, particularly, due to increased fill factors. The obtained data strongly suggest that
addition of ODT leads to precipitation of pure P3HT and formation of the electron-blocking
interlayer between the anode and the photoactive blend.
Similarly, pure fullerene phase placed between the aluminum cathode and the fullerene/polymer
blend can serve as a hole-blocking interlayer. To achieve this, fullerene derivatives with higher
solubilities than PCBM and P3HT were applied as additives. These additives also improved
performance of the devices.
Finally, we designed organic cocktails comprising co-dissolved “highly-soluble fullerene”,
PCBM, P3HT and ODT. When solvent is evaporated from such a cocktail, a thin film of the pure
P3HT is formed first, then PCBM/P3HT blend layer is growing up and, at the end, almost pure
“highly soluble fullerene” is deposited on the top. Thus we showed that our cocktail approach
gives “anode//polymer/fullerene+polymer/fullerene//cathode” device architectures with the
improved active layer morphologies and photovoltaic performances.
88
PHOTODISSOCIATION OF COMPLEXES OF QUANTUM DOT /
ORGANIC MOLECULES EMBEDDED IN THIN POLYMER FILMS
E.V. Ushakova, A.O. Orlova, A.V. Baranov
St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
a_v_baranov@yahoo.com
Last years hybrid nanostructures comprised bonded quantum dot (QD) and organic molecules
combined attract great attention. Such complexes is considered as a perspective structures for
fabrication of luminescent sensors for quantitative analysis of presence of different analytes in
liquid solutions.
We have studied one of such luminescent nanosensors for detection of some metal ions in water
solution. The sensor is based on complex QD/PAN, where QD is the CdSe/ZnS core/shell
quantum dot and PAN is the azo dye molecule, 1-(2-pirydilazo)-2-naphtol, embedded in thin
polymer film. In absence of ions QD luminescence is practically quenched due to resonant
nonradiative energy transfer from QD to molecule. When the film is placed into water solution
containing metal ions they diffuse into film and stimulate dissociation of the QD/PAN
complexes. As a result, QD luminescence is arisen with intensity proportional to the ion
concentration in analyzed solution. Since the luminescence is excited by optical radiation, the
question is arisen about possible photodissociation of the sensor and its influence on parameters
of the luminescence response of the sensor. This information is important for determination of
the excitation light parameters needed for sensor utilization for analytical applications.
In the report we well present results of comparative studies of changes in luminescence intensity
and luminescence lifetime of QD/PAN complexes embedded in polymer films under exposure of
laser light. The experiments were performed by the use a laser scanning luminescent microscope
with possibility of time-resolved measurements (Microtime100, PicoQuant) at room temperature.
It has been found that photodissociation of QD/PAN complexes with appearance of free
luminescent QDs takes place in studied systems under strong laser irradiation. The
corresponding incident light intensity and energy dependencies of QD luminescence intensity
and lifetime will be presented. Finally we found acceptable parameters of incident light allowing
utilization QD/PAN complexes as a dissociative luminescent sensor.
89
SERS, SPECTROPHOTOMETRY AND AFM STUDY
OF PHOTOCHROMISM OF SPIROCYCLIC COMPOUNDS
ON NANOSTRUCTURED METAL FILMS
G.T. Vasilyuk1, S.A. Maskevich1, A.E. German1,
I.F. Sveklo1, B.S. Lukyanov2, L.A. Ageev3
1 - Y. Kupala Grodno State University, Grodno, Belarus
2 - Institute of Physical and Organic Chemistry, South Federal University,
Rostov-on-Don, Russia
3 - V. Karazin Kharkiv National University, Kharkiv, Ukraine
vasilyuk@grsu.by
Spiropyrans and spirooxazines are compounds performing photochromic properties in solutions
as well as in solid matrices. In the presence of metal these compounds receive additional
important properties. Chelate complexes spirocyclic molecules with metals allow to receive
thermostable photoswitches. At adsorption of molecules on metal surface with nanosized
roughnesses the enhancement of photochemical processes as well as the enhancement of Raman
scattering signal are observed also [1, 2]. Use composit nanopartices can as to provide necessary
thermal stability photochromic molecules thanks to thermal energy sorbtion by a metal kern of
such particle, and to increment efficiency of phochromism at the expense of a enhancement of an
electromagnetic field near to a metal surface.
In the capacity of active substrates are used sols and granular silver films (SF) as well as
photosensitive thin films of silver chloride with impurity granular silver (films AgCl-Ag). They
can ensure additional (at the expense of collective effects) a enhancement of a Raman scattering
signal thanks to presence periodic nanostructuring, optical attained. The photoinduced
phenomena occuring in films AgCl-Ag, have similar features with the phenomena in
photochromic materials and can be used for demonstration of various resonant nonlinear effects.
A photosensitivity of thin-film system AgCl-Ag is interesting also in itself as it is related to
discrete state Ag in film AgCl and can be referred to a number of the abnormal phenomena
(nanophotonics), observed in medium with nanosized particles.
In the present work by surface enhanced Raman spectroscopy (SERS), spectrophotometry and
atomic-force microscopy (АFМ) methods features spirocyclic molecules photochromic
conversions near nanostructured metal surfaces are studied, and also receive for this purpose
original nanostructured systems and studied their structural (surface morphology) and optical
(including enhancing) properties.
Efficiency raise of photochromic conversions near nanostructured metal surfaces is revealed.
SERS spectra of various spirocyclic compounds on various types of nanostructured systems
(granular SF, films AgCl-Ag) are received and interpreted. The SERS bands assigned to in-plane
vibrations, transforming on unit irreducible representation Ag are most intensive.
This work was supported by Byelorussian Foundation for Basic Research (Grants F07K-096,
F08R-229) and Russian Foundation for Basic Research (Grant 08-03-90029 Bel)
1. Nitzan, A., Brus, L.E., J. Chem. Phys., 1981, vol. 74, p. 5321
2. Nitzan, A., Brus, L.E., J. Chem. Phys., 1981, vol. 75, p. 2205
90
DYNAMICS OF PHOTOPROCESSES IN NOVEL BIFUNCTIONAL
SALICYLIDENEIMINOSPIRONAPHTHOXAZINES
N.L. Zaichenko1, P.P. Levin2, I.R. Mardaleishvili1, A.I. Shiyonok1,
L.S. Kol’tsova1, O.Yu. Os’kina1, A.S. Tatikolov2
1 – N.N. Semenov Institute of Chemical Physics RAS, Moscow, Russia
2 – N.M. Emanuel Institute of Biochemical Physics RAS, Moscow, Russia
zaina@polymer.chph.ras.ru
A row of novel photobifunctional compounds (PBC) which molecules combine two different
photosensitive fragments – a spirooxazine moiety and substituted salicylideneimine (SA) one were synthesized for the first time. Two different photoprocesses can occur in these compounds
after UV-light absorption: C-O spiro-bond dissociation and excited state intramolecular proton
transfer (ESIPT).
Me Me
MeMe
N
N
H O
H O
N
N
N
N
O
CH
O
CH
N
Me
Me
(3)
(1) R = H
R
(2) R = NO2
Three photoproducts, namely open merocyanine form of spironaphtoxazine fragment linked with
enole (BE ) or cis-keto-form (BKc ) of SA fragment and trans-keto-form of SA linked with closed
spiroform of spirooxazine (AKt), were registrated in solutions by nanosecond laser fleshphotolysis. Spectral-kinetic characteristics of these photoproducts were studied, their quantum
yields were measured.
All three above mentioned photoproducts with λmax = 500 (АКt), 600 (ВE) и 620 нм (BKc).
were observed in MeOH solutions after 337 nm pulse excitation in the time interval ≥ 10 ns.
Only two photoproducts - ВE with λmax = 600 nm and АКt with λmax = 500 nm – were observed
in toluene solutions of PBCs at the same conditions.
It was established that two photoprocesses –spirocycle cleavage and ESIPT – are concurrent and
independent in the PBCs under study.
Solvent nature has a dominant influence on the number of photoproducts of PBCs photolysis,
kinetics and mechanism of their bleaching reactions. In MeOH solutions a formation of BKc form
from BE* is possible.
Influence of the substituents in SA fragment of PBC molecules on the ratio of two
photoprocesses and the lifetime of photoproducts is discussed.
Presidium of RAS (Program «Development of methods for synthesis of chemical compounds and
creation of new materials») financially supports this work.
91
PHOTOLUMINESCENCE KINETICS OF
(ZINC)TETRAPHENYLPORPHYRIN-FULLERENE
CHARGE-TRANSFER COMPLEXES
I.B. Zakharova1, G.M. Ermolaeva2, O.E. Kvyatkovskii3, L.V. Belyakov3
1 - State Polytechnic University, St.Petersburg, Russia
2 - RC "S.I. Vavilov State Optical Institute", St.Petersburg, Russia
3 – A.F. Ioffe PTI RAS, St.Petersburg, Russia
zakharova@rphf.spbstu.ru
Porphyrin-fullerene dyads and complexes have been the subject of intense research as artificial
systems that efficiently convert sunlight into energy [1]. In this work the interaction of molecular
components, as well as optical and photoelectrical properties of С60-Zn(II)tetraphenylporphyrin
(ZnTPP) thin films and solutions has been investigated. Ab initio calculations of optimized
geometry and electronic structure ZnTPP-C60 have been carried out. It is shown that due to the
acceptor properties of С60 molecule, the pair С60 - ZnTPP forms a stable charge transfer complex
with a binding energy of 0.6 эВ, distance between the molecular components of 0.25 nm and the
amount of transferred charge of 0.4 ē, HOMO-LUMO gap Eg is 1.38 eV.
The photoluminescence (PL) spectra were measured for the toluene solutions and thin films,
which were grown by in the quasiequilibrium conditions on the CaF2, Si, KBr substrates. The
UV-Vis-NIR absorption studies and Raman scattering investigations are described in [2]. The
formation of the charge-transfer complex leads to the quenching of the photoluminescence in the
region of ZnTPP lighting (620 nm) and to the increase of luminescence intensity in the region
peculiar to C60 (750 nm), as well as to the changes in fluorescence kinetics. It is shown that C60ZnTPP PL peak position strongly depends on substrate type. PL kinetics has been explored both
on the wavelength of 560 nm corresponding to the absorbance maximum for free ZnTPP
molecule and 343 nm where the С60 molecule has the maximum. We have found that the PL time
decay is an order of magnitude lower for the ZnTPP thin solid films than that for the ZnTPP
toluene solutions. The time decay constant is found to be 300 ps, which is typical for the π*-π
transitions. We have found a phenomenon of luminescence condensation: the response duration
decreases with the increase of the stimulating emission power density. The kinetic curves
demonstrate the two- stage photoinduced intramolecular charge transfer with time constant
about 2 ns.
LITERATURE
1. Guldi D.M. Pure Appl. Chem., 2003, 75, 1069-1075.
2. Zakharova I.B., Donenko E.G., Biryulin Yu.F., Sharonova L.V. Fullerenes, nanotubes and
carbon nanostructures, 2008, 16, 424-429.
92
PHOTOCHEMICAL PROCESSES IN SELF-ORGANIZED
MULTIPORPHYRIN COMPLEXES
E.I. Zenkevich1, E.I. Sagun2, V.N. Knyukshto2, C. Von Borczyskowski3
1 - National Technical University of Belarus, Minsk, Belarus
2 - B.I. Stepanov Institute of Physics, Minsk, Belarus
3 - Institute of Physics, Chemnitz University of Technology, Chemnitz, Germany
zenkev@tut.by
At present, supramolecular chemistry is reaching highly elaborate levels of sophistication and the
analysis of the cooperative behaviour of subunits within controlled spatial assemblies involving
molecular recognition, catalysis, molecular devices, etc. According to the nowadays conception, the
co-ordination of the porphyrin metal ions to additional ligands via amino acid side chains in natural
protein complexes might affect the excited states deactivation of porphyrins, the rate constants and
the efficiency of the energy migration (ET) and charge separation as well as might influence on the
interaction of the porphyrin subunits with external reactants including molecular oxygen (O2). The
goal of the report is the comparative analysis of the extra-ligation influence on the deactivation of S1and T1-states for nanoscale self-assembled multiporphyrin arrays (triads and pentads) as well as on
their interaction with molecular oxygen in solutions using steady-state, laser nanosecond fluorescent
and pump-probe kinetic data and direct measurements of singlet oxygen (1∆g) emission (1.27 µ).
Triad
Pentad
The formation of self-assembling porphyrin
triads and pentads has been succeeded using
two-fold extra-ligation of both central Zn ions
of the dimers with two nitrogens of mesopyridyl rings in the corresponding di- and tetrapyridyl-containing free base porphyrin extraligands based on a “key-hole” principle. The
triads and pentads were formed at 295 K during
a titration of the dimer solution (C∼1⋅10-6
M÷4⋅10-6 M) with
an extra-ligand solution (C∼0.3⋅10-4 M÷2⋅10-4 M).For pyridinated dimers (precursors of the triads
and pentads) at 295 K T1-states quenching by molecular oxygen depends on the spacer flexibility and
donor-acceptor interactions with pyridine.
The non-radiative relaxation of the dimer S1-state in self-assembled triads and pentads takes place
within ∼1.6 ps with respect to τS=1,2 ns for individual dimer. The main reason of this quenching is
due to the competition of the energy migration (EM) and photoinduced electron transfer (PET)
processes to the extra-ligand depending on the spectral-kinetic and redox properties of the interacting
subunits as well as on temperature and the solvent polarity. Thus, the direct population of the dimer
T1-state via intersystem crossing S1(1Dimer*)∼∼> T1(3Dimer*) with a rate constant of kISC∼(57)⋅107s-1 is probably slow. Instead, fast EM and ET processes are followed by the effective
population of the extra-ligand T1-state.
The role of structural organisation of triads and pentads is most readily understood upon their
interaction with molecular oxygen in liquid solutions at 295 K. Bimolecular rate constants of the
extra-ligand T1-states quenching by O2 are decreased by 1.4-1.8 times with respect to those found for
individual monomeric porphyrins. In addition, quantum yields of singlet oxygen generation by triads
and pentads are noticeably smaller relative to the corresponding data for free base porphyrin
monomers. These effects are explained by the screening action of a strongly quenched Zn-porphyrin
dimer subunit limiting the access of oxygen molecule to the excited extra-ligand.
This work was supported by Belarus Programs Nanoteckh 6.18 and KMS 17as well as by ECO-NET
Project (program No 18905YD).
93
SYMPOSIUM “MOLECULAR PHOTONICS”
Dedicated to Academician A.N. Terenin
ORALS
INTERMOLECULAR INTERACTIONS AND PHOTOPROCESSES
IN MOLECULAR SYSTEMS
V.Ya. Artyukhov, G.V. Mayer
Tomsk State University, Russia
artvic@phys.tsu.ru
In molecular spectroscopy and luminescence the basic displays universal (physical) ММВ
consist in changes of a position, a form and an intensity of bands of radiation and absorption.
Specific (quasi-chemical) ММВ can cause occurrence (or disappearance) new bands of
absorption and a luminescence.
From the end of 80th years we carried out theoretical researches of the phenomenon of electronic
excitation energy transfer in bichromophoric organic compounds and molecular systems. During
researches it has been developed quantum-chemical model of studying of the orbital nature and
spatial localization of electronic states and features of course of photoprocesses in such systems.
Determined that necessary condition for realization intermolecular (interchromophoric)
photoprocess is a delocalization of wave functions of electronic states, participating in
photoprocess. This delocalization results from intermolecular interaction a component
(fragments) system.
It is shown, that intermolecular photoprocesses on the nature (as the interaction initiating
electronic transition) do not differ from the intramolecular photoprocesses. Quantum-chemical
techniques of an estimation of the rate constants of intramolecular photophysical processes can
successfully be applied to estimate the rate constants of intermolecular photophysical processes
Intermolecular nonradiation energy transfer of electronic excitation is only a special case of
influence of intermolecular interaction on spectral-luminescent and photochemical properties of
organic compounds. The correct description of mechanisms and laws of intermolecular
photoprocesses is necessary at research of suppression of a luminescence (including,
concentration), charge transfer complexes and any polymolecular systems.
In the given report influence of intermolecular interactions on electronic states and spectralluminescent properties of bimolecular systems is considered. It is shown, that as the initial stage
of quantum-chemical research of this influence the analysis of spatial structure of one-electronic
states (molecular orbitals) is necessary. The assumption of an opportunity of neglect of overlap
of molecular orbitals in contact complexes is incorrect and leads to fallacies on the photophysics
of such complexes.
94
AN EFFECT OF THE THIRD COMPONENT
ON THE LUMINESCENCE OF THE NANO-SIZED
NAPHTHALENE–CYCLODEXTRIN COMPLEXES
V.G. Avakayn1, V.B. Nazarov2, T.G. Vershinnikova2,
V.Y. Rudyak1, M.V. Alfimov1
1 - Photochemistry Center RAS, Moscow, Russia
2 - Institute of the Problems of Chemical Physics RAS, Chernogolovka, Russia
avak@photonics.ru
luminescence, rel.un.
A slow formation of the nano-sized complexes of the composition 2:2 occurs in the water
solution of naphthalene in the presence of beta-cyclodextrin (b-CD). In the complexes, two
naphthalene molecules are oriented parallel to each other and exhibit an eximer fluorescence
(EF) [1]. We observed that at an addition of o-carborane, as the third component, eximers are
formed rather and even at the lower concentrations (≤10-4М) (see Fig.). However, EF is not
12
observed if the order of adding components is
changed: b-CD – o-carborane – naphthalene.
2
10
An addition of adamantane as the third
8
component results in to destruction of the
3
complexes of composition 2:2 and to
6
appearance of the long lived phosphorescence
4
at room temperature (PRT) visible without
1
eliminating oxygen [2,3]. Quantum-chemical
2
calculations of the structure and energetics of
0
the naphthalene – b-CD complexes of various
300
350
400
450
500
550
wavelength, nm
composition at the presence and lack of the
third components showed that o-carborane
Fluorescence spectra of naphthalene-d8 (C=10-4M)
stabilizes complexes of the composition 2:2
in water solution at 20°С (1), in the presence of
because it is inserted at them from the side of
b-CD (2),and b-CD and o-carborane (3)
the narrow entrance to the CD cavity due to the
size of o-carborane molecules. The destruction of the complexes of the composition 2:2 by
adamantane occurs due to it possibility to embed into the binary complex naphthalene – b-CD,
precursor of the 2:2 complex, resulting in the complex of the composition 1:1:1. The latter along
with its surrounding the very strong adamantane – b-CD complexes forms the nanoparticle
revealing RTP at the presence of oxygen. However, o-carborane whose molecules are bigger
than adamantane is not capable to form complex 1:1:1 and RTP is not observed at the presence
of o-carborane. Therefore, changing the structure of the third component we have a possibility to
control by the complex structure and as well by a kind of luminescence.
Financial support from the Russian Foundation for Basic Research (Grant RFBR No. 09-0300404) is gratefully acknowledged.
1. V. B. Nazarov, V. G. Avakyan, T. G. Vershinnikova, M. V. Alfimov, Izv. Acad. Sci., ser.
khim. 2000, No. 10, P. 1716.
2. V. B. Nazarov, V. G. Avakyan, T. G. Vershinnikova, M. V. Alfimov, Izv. Acad. Sci., ser.
khim. 2003, No. 4, P. 869.
3. V. B. Nazarov, V. G. Avakyan, E. I. Bagrii, T. G. Vershinnikova, M. V. Alfimov, Izv. Acad.
Sci., ser. khim. 2005, No. 12, P. 2661.
95
PHOTOCHROMIC NANOPARTICLES:
PROPERTIES AND APPLICATIONS
V.A. Barachevsky
Photochemistry Center RAS, Moscow, Russia
barva@photonics.ru
The phenomenon of photochromism is of a considerable theoretical and scientific interest owing
to reversible photoinduced transformations of substances. It was a base for a lot of applications.
This paper is devoted to the analysis of study results, including own, carried out in recent years
in the field of the development and properties study of photochromic nanoparticles. .
At first, the main types of photochromic nanoparticles as well as methods of their preparation are
discussed. Thermally relaxation spirocompounds and thermally irreversible diarylethenes and
fulgides were used as photochromic components.
Aggregates of the photoinduced merocyanine form of spirocompounds are characterized by
specific spectral manifestations which provide the development of photochromic media for
frequency-selective optical memory, nonlinear transformation of laser irradiation and making
photocontrolled photon crystals.
Photochromic coverings of Au и Ag nanoparticles exhibit a different efficiency of
phototransformations dependent of a distance between a nanoparticle surface and photochromic
molecules. This distance determines an efficiency of an energy transfer between photochromic
molecules and nanoparticles. These photochromic systems manifest an interference of the
photoinduced absorption change of photochromic compounds and absorption caused by a
plasmon resonance. This phenomenon may be used for the development of a new method for
nondestructive readout of optical information recorded in photochromic media. The phenomenon
of surface plasmon polarization was used for the development of small-size and effective
plasmon light modulators.
One of the important applications of photochromic metal-containing nanoparticles is the
development of photocontrolled nanoconductors changing their conductivity owing to
photoinduced changing the length of conjugated bonds into photochromic molecules. The same
application can be realized for single-walled nanotubes functionalized by photochromic
molecules.
Photochromic molecular inclusion complexes provide a required long life-time of the
photoinduced merocyanine form for spirocompounds due to formation of intermolecular
hydrogen bonds as well as high efficiency of photochromic transformations for diarylethenes
owing to the change of a concentration ratio for two isomers of the open form.
Other types of photochromic nanoparticles are of special interest for the development of
multilayer recording media with very the high concentration of photochromic compounds for
three-dimensional bitwise working optical memory. Optical memory of super high information
capacity may be made with the use of photochromic recording media possessing a photochromic
periodic nanostructures, including quantum dots (QDs), particularly CdSe/ZnS, providing
photoinduced emission modulation due to the resonance transfer of photoexcitation energy.
Above discussed advances extend an area of application of photochromic materials and make a
contribution into the development of organic nanophotonics.
96
PHOTONIC MOLECULAR LOGIC GATES
M.F. Budyka
Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
budyka@icp.ac.ru
Reduction of the size of nanodevices inevitably achieves physical and technological limits,
below which exploitation of the 'top-down" principle is impossible. Another - "bottom-up" approach demands creation and research of the various molecular systems, capable of operating
as signal conductors, switches, diodes, elements of memory, and also logic devices.
Molecular logic gate (MLG) is a switch, whose input and output signals can accept only values
of "0" or "1". Dependence of values of output signals on input is defined by the truth table of the
logic (Boolean) function.
For the majority of known MLGs the role of input signal carries out some chemical impact addition of an acid or alkali, ions of metals, other reagents. Application of such devices
practically is limited by solutions.
In completely photonic MLGs, the role of input and output signals is carried out by photons.
Impact on the system consists in irradiation by light of definite wavelength, and readout is made
on optical density or luminescence. There are known examples of completely photonic molecular
gates which are capable of performing "AND", "OR", "XOR", "INHIBIT" logic operations, and
more complex functions of half-adder, encoder-decoder.
For maintenance of cyclicity of work in photonic MLGs reversible photochemical reactions are
used among which photocyclization/photodecyclization of derivatives of spiropyran,
dihydropyrene, dihydroindolizine, dihetarylethene, photoisomerization of derivatives of stilbene
and azobenzene, photoinduced electron transfer .
The light of different wavelength can be used for readout of output signal of photonic MLG. The
response can be various, and thus, it is possible to make different logic operations with the help
of the same molecular system. This unique property - compatibility of several logic gates in one
device or reconfigurability of logic gate on different type of work - is essentially unattainable for
currently used semi-conductor elements where for each logic operation the separate device is
necessary.
For construction of complex nanosized blocks (nanophotonic devices) from separate MLGs, the
self-organization of molecular systems into supramolecular ensembles is supposed to be used.
The general problem in this case is the organization of interaction between different MLGs, i.e.
signal transfer from one MLG to another. The role of an information carrier in photonic MLG
can play singlet-singlet or triplet-triplet energy transfer or photoinduced electron transfer.
The work was supported by the Russian Foundation for Basic Research (grant no. 07-03-00891).
97
EFFECT OF SOLVENT POLARITY ON THE PRIMARY
PHOTOPROCESSES OF CYANINE DYES
A.K. Chibisov
Photochemistry Center RAS, Moscow, Russia
chibisov@photonics.ru
2
5
2
∆A / ∆A(100%)
Photophysical processes and the primary photochemical reactions of cationic and anionic
thiacarbocyanine dyes which take place in solvents of different polarity are considered. Cationic
thiacarbocyanines containing iodide as a counter ion exhibit in less polar solvent (toluene +
DMSO) strong enhancement of the quantum yield of intersystem crossing ΦТ of the dyes due
to “heavy atom effect”
200
in ion pairs. An increase
S
S
100
+
of ΦТ is accompanied by
N
N
decreasing
of both the
CH
CH
2
quantum
yield
of
X (Cl , I )
Relative yield of cis-isomers (■)
fluorescence Φf and
1
and triplets (▲) for Dye with X- =
trans→cis
isomeri0
I and X = Cl (□ and ∆) in the
zation Φisomer [1]. Anio0
20
40
60
80
100
mixture of DMSO with toluene
nic sulfopropyl-9-ethyl
DMSO, vol. %
thiacarbocyanines in less
5
-
-
-
polar solvent (dioxane) are characterized by high quantum yield Φf and Φisomer and low ΦТ value.
Passing from less polar to solvent of medium and high polarity results in the decrease of Φf and
Φisomer. The quantum yield of intersystem crossing is extreme low and hence the main pathway
of deactivation of the excited singlet state is internal conversion. In the solvent of medium
polarity the reaction of trans →cis isomerization which proceeds via the excited singlet state
competes with electron transfer occurring between the dye in the triplet state and methylviologen
[2]. Anionic sulfopropyl-9-ethylthiacarbocyanines also demonstrate propensity to aggregation
in water and particularly to
dimerization. Principal feaEt
S
S
∆A
OMe
+
ture of the dimers is their
N
N
ability to intersystem crossing
(CH ) SO
(CH ) SO
and the lack of fluorescence
+
(C H ) NH
[3]. Dimers in the triplet state
T-T absorption spectra of Dye in
exhibit the ability to electron
λ, nm
water at different time after
transfer with an appropriate
laser pulse
donor and/or acceptor and
hence the dimers serve as photosensitizers of redox reactions [4].
0.2
100 ns
7 µs
35 µs
0.0
2 3
3
2 3
3
-0.2
2
5 3
400
500
600
700
The author thanks Prof. B.I. Shapiro for providing cyanine dyes. This work was supported by
RFBR (grant 09-03-00170-a) and DFG.
References:
[1] A.K. Chibisov, D.A. Voznyak, N.Kh. Petrov, M.V. Alfimov. High Energy Chemistry, 2009,
v. 43, p.38 (English translation).
[2] L.S. Atabekyan, D.A. Voznyak, G.V. Zakharova, A.K. Chibisov. High Energy Chemistry,
2008, v. 42, p.454 (English translation).
[3] A.K. Chibisov. High Energy Chemistry, 2007, v. 41, p.200 (English translation).
[4] A.K. Chibisov, T.D. Slavnova, G.V. Zakharova, H. Görner. High Energy Chemistry, 2007,
v. 41, p.344 (English translation).
98
PHOTONICS OF HEMOGLOBIN AND MYOGLOBIN ACTIVE CENTERS
B.M. Dzhagarov, S.V. Lepeshkevich
B.I. Stepanov Institute of Physics NAS, Minsk, Belarus
bmd@imaph.bas-net.by
Mutual action of tetrameric protein hemoglobin (Hb) and monomeric protein
myoglobin (Mb) provide for the harvest, transfer and storage of molecular oxygen.
The active centre (prosthetic group) of these proteins is heme (iron-protoporphyrin
IX complex). In biophysics, biochemistry and biophotonics Hb and Mb are
possibly the main models to elucidate the mechanism of cooperative nonlinear
interaction in proteins and to determine of the function – structure – dynamics
linkage.
In our lecture a special attention is paid to the heme-O2 recombination process
taking place after fast photodissociative breaking of bond between O2 and ion
Fe(II) located in the active center. We present results of nano-, pico-, and
femtosecond flash-photolytic studies of excited states and relaxation processes,
photodissociation quantum yields, efficiencies and rates of the monomolecular
geminate and bimolecular stages of oxygenation reaction in Hb and Mb in
solutions and sol-gel matrices. On the basis of the results a full description of
oxygen motion in protein matrix will be given and the kinetic mechanism of
protein self-regulation of ligand binding will be discussed.
99
ACTIVITY AND SELECTIVITY OF PHOTOCATALYSTS
A.V. Emeline
V.A. Fock Institute of Physics, St.Petersburg State University, Russia
emeline_av@hotmail.com
The activity of photocatalysts is characterized by quantum yield of corresponding heterogeneous
interfacial photoreaction defined as a ratio between the number of chemically transformed
molecules (ions), Nm, (per time unit) and the number of photons absorbed by photocatalyst, Nhv
(abs), (per time unit):
dN m
dt
Φ =
dN hν ( abs )
dt
Thus, this parameter characterizes the ability of photocatalyst to transform the energy of
absorbed photons into chemical transformation that determines that activity of photocatalyst. In
general, the quantum yield of heterogeneous photoreaction is a function of wavelengths of
incident light. Therefore, to answer the question, which photocatalysts is more active, one needs
to know the spectral distribution of the quantum yield for corresponding photoreaction. The
qualitative interpretation of such phenomenon based on one-dimension model considering
charge carrier photogeneration, decay, diffusion and surface interaction with molecules will be
given during presentation. Experimental spectral dependencies of the quantum yield obtained for
different interfacial photoreactions in both gas-solid and liquid-solid heterogeneous systems
(such as, phenol(s) – TiO2 and N-, Fe-, Pt- doped TiO2, phenol(s) – ZrO2; hydrogen, oxygen –
TiO2 and N- doped TiO2, ZrO2 and F-doped ZrO2) will be presented and discussed in frame of
the model.
Another significant parameter characterizing the photocatalyst behavior is its selectivity defined
as a ratio between the number of molecules of given product, Ni, formed during reaction (per
time unit) and the number of reagent molecules, Nr, involved into reaction (per time unit):
dN i
dt
Si =
dN r
dt
Thus, this parameter characterizes the ability of photocatalyst to drive the interfacial
photoreaction toward the certain reaction product. As evident from experimental data, this
parameter also depends on the wavelengths of actinic light. Corresponding experimental
dependencies will be demonstrated during presentation. Qualitative explanation will be given on
the basis of model considering the spectral variation of the electron transfer pathways.
Spectral activity and selectivity of photocatalysts
100
TETRAPHENYLPORPHYRIN DERIVATIVES STRUCTURE
AND MOLECULE SURROUNDINGS DEPENDING
ON LUMINESCENT CHARACTERISTICS
E.G. Ermolina1, R.T. Kuznetsova1, R.M. Gadirov1, G.V. Mayer1,
Yu.V. Korovin2, N.N. Semenishin2, N.V. Rusakova2
1 - Tomsk State University, Tomsk, Russia
2 - Bogatskiy Physical-Chemical Institute, Odessa, Ukraine
yaskolka@inbox.ru
A broad range of cyclotetrapyrrol applications includes oxygen sensors and OLEDs. For these
purposes substances with high phosphorescent yield are necessary. Ealier the luminescent
properties of some tetraphenylporphyrin (TPP) complexes were studied, essential
phosphorescent intensity increasing caused by “heavy ion” introduction is shown. In this paper
10 free bases and metalcomplexes of complexon and Lu(III)-complexonate containing TPP were
synthesized and studied in compare with ZnTPP. Co(II), Ni(II), Cu(II) and Zn(II) are central
ions.
Lu(II) ion introduction has not influence on the absorbance and luminescense spectra location.
Free bases absorption contains 4 Q-bands. Absorption of metalcomplexes holds B-band at 420
nm and Q-band at 550 nm. Substitution essential influence on protonation efficacy in basic and
excited states is ascertained. Concentration peculiar properties of unfilled d-shell ion (Co(II),
Ni(II)) containing complexes in liquid and frozen solutions are poined out.
Luminescence spectra location under Q-band excitation slightly depends on metal nature and
greatly – on temperature. Luminescence efficacy changes noticeable. Luminescence efficacy
from high states under B-band excitation depends on substitution.
Long-live radiation of frozen solutions contains concuring with fluorescence location
component. It’s life-time two times less than phosphorescence life-time.
Phosphorescence efficacy dependence on temperature and oxigen presence is ascertained.
Phosphorescence quantum yield and life-time values are estimated.
The work is supported by The Russian Foundation for Basic Research ( project 08-02-90003).
101
SPACE RADIATION IMPACT ON PREBIOTIC SYNTHESIS AND
STABILITY OF BIOORGANIC MOLECULES: COMPARATIVE STUDY
N.B. Gontareva, E.A. Kuzicheva
Laboratory of exobiology, Institute of Cytology RAS, S.-Petersburg, Russia
ngontar@mail.cytspb.rssi.ru
Study of space irradiation impact towards main organic molecules is the major task of future
space flight experiment, planned for performing onboard Russian space station “Bion-10M”. Our
latest investigations were aimed to work out strategy for the full-scale orbital experiment in order
to avoid any mistakes and data loss. “Bion-M” experiment covers different aspects of chemical
behavior of organic molecules embedded in mineral matrix in water-free conditions as the
respond to space radiation.
Experimental studies of the possible ways and mechanisms of bioorganic substances (BOS)
survival and synthesis in different radiation conditions are closely connected with investigating
of prebiotic evolution pathways both at the primitive Earth and other Solar System planetary
bodies. Besides, it is important to test whether organics in Earth orbit could be protected by
extraterrestrial minerals.
This research has been carried out onboard different Russian space stations (Bion, Cosmos and
Mir) with various duration, altitude and radiation conditions. In each case the experimental
hardware has been displayed on the outer cover of the space stations to experience the impact of
the cosmic radiation over molecular samples, free or combined with minerals of the
extraterrestrial origin. After retrieval, HPLC analysis, confocal microscopy and mass
spectrometry techniques were employed to identify qualitatively and quantitatively the products
in reaction mixture. The special emphasis has been given to the stability of the initial molecules
(peptides and nucleosides) and their decrease rate as the respond to the harsh orbital conditions.
To identify and evaluate the principal source of energy in open space responsible for peptides
and nucleotides destruction and synthesis reaction laboratory experiments were performed. Dry
films containing aminoacids Gly+Trp, Trp and nucleoside+phosphate were exposed on the outer
surface of orbital stations. Identical films were exposed to the different radiation types in
laboratory experiments. Different types of energy needed for reaction’s triggering have been
investigated in respect with the highest response of biochemical systems. Most destructive and
most productive types of energy impact were identified in given radiation conditions. The
presence of extraterrestrial minerals (lunar soil, meteorites Allende and Murchison) both in flight
and in ground experiments decreased the destructive rate of BOS. Presumably these results
favour the protective role of mineral bed from the destructive impact of cosmic radiation. These
experiments make important contribution to the problem of life origin and prove the possibility
of organic substances’ survival in space conditions.
From the other hand, the radiation behavior of BOS on the Earth orbit could have truly applied
meaning. For instance, the formation of uridine dimers in the exposed samples could serve as an
immediate indicator of the high radiation level (biological dosimeter). This phenomenon was
traced in our in-flight experiments and could be utilized during manned missions’ planning in
nearest future.
102
INTENSITIES OF IR BANDS OF SURFACE OH GROUPS OR OF THE
C-H STRETCHING BANDS OF ADSORBED MOLEQULES – A NEW
SPECTRAL CRITERION OF ACTIVATION OF CHEMICAL BONDS
IN HETEROGENEOUS ACID CATALYSIS VIA THEIR POLARIZATION
V.B. Kazansky, I.R. Subbotina
IOC RAS
vbk@ioc.ac.ru
The low-frequency shifts of IR bands of adsorbed molecules are traditionally used as a spectral
criterion of activation of chemical bonds in heterogeneous acid catalysis. In addition in our last
works it was suggested to use for this purpose also intensities of IR bands which are connected
with polarization of chemical bonds upon their stretching or bending resulting from vibrational
excitation. Utilization of this new spectral criterion is most attractive for heterogeneous acid
catalysis, where chemical activation of adsorbed molecules just results from their polarization by
the active sites.
Indeed, it is well known that the extinction coefficients of IR bands are proportional to the
squares of derivatives of dipole moments of chemical bonds resulting from their normal
vibrations. Interaction of the oscillating dipole moments resulting from stretching or bending
vibrations of chemical bonds with IR irradiation just results in its absorption. In this case the
vibrational intensities of IR bands correspond to polarization of chemical bonds resulting from
their stretching or bending.
The same parameters are also involved in reaction coordinates of catalytic transformations of
adsorbed molecules. Therefore, if the low-frequency shifts of IR bands are connected with their
higher intensities, their weakening just results from their polarization upon interaction with the
active sites.
The present report presents several examples illustrating utility of this new approach for
interpretation of IR spectra of adsorbed molecules. First of them is devoted to using of intensities
of IR bands of O-H stretching vibrations as a measure of of their acidity strength [1]. The
obtained results indicated that intensities of O-H stretching vibrations of the bridging acidic O-H
groups are more than one order of magnitude higher than those of the less acidic silanol groups.
Therefore, the acidity strength of Broensted acid sites in zeolites can be measured by OH
stretching intensities without generally used application for this purpose of adsorption of weak
bases.
Another example concerns the study of adsorption of light paraffins by cationic forms of the high
silica zeolites. In this case the obtained results indicated the anisotropy of polarization of
different C-H vibrations. For the zinc form of ZSM-5 zeolite this results in the very high
intensity of the low-frequency shifted band from C-H vibrations indicating strong polarization of
this vibrational mode by zinc cations, while at elevated temperature this results in heterolythic
dissociative adsorption of light paraffins [2].
REFERENCES
1. V.B.Kazansky, A.I.Serykh, V. Sommer-Herledan, J.Fraissard, PCCP 2003, 966-969.
2. I.R.Subbotina, V.B.Kazansky, Kinetics and Catalysis 2008, v. 49, 149-156.
103
THE EVOLUTION OF PHOTOCHEMICALLY GENERATED
RADICAL PAIRS IN GLASSY POLYMERS: RECOMBINATION
FEATURES IN MACROMOLECULAR NANOREACTORS
E.Yu. Khavina, V.B. Ivanov
Institute of Chemical Physics RAS, Moscow, Russia
kelizabeth@ya.ru
Radical pairs (RP) formed in photochemical processes with participation of low molecular
reagents or chromophore groups are a key intermediate product of free-radical reactions in
controlled degradation or modification of polymer materials of important technical application.
Therefore, the investigation of the role and features of spin, molecular and chemical dynamics in
processes of their evolution is an actual problem. In our work the reaction of recombination of
ketyl and aminyl radicals formed during UV-irradiation of glassy polymer films – poly(methyl
methacrylate) (PMMA), poly(vinylchloride) (PVC), polystyrene (PS) and cellulose triacetate
(CTA) containing aromatic ketones (benzophenone and a number of its p-substituted derivatives)
and several aromatic amines (diphenylamine, its derivatives and quinolines of different structure)
is studied.
It is shown that triarylcarbinols, identified after treatment of irradiated films with HCl by
characteristic visible absorption spectra as relevant triarylmethane dyes, are formed as a result of
recombination of ketyl and aminyl radicals. Quantum yields of the reactions are determined. It is
shown that introduction of strong electron-donor substituents in p-position of ketone,
significantly decreasing affinity to electron, leads to a reduction of the RP yield and, as a
consequence, the yields of recombination products. The process is found to proceed via ketyl
radical attack of aminyl radical in the p-position, thus aromatic amines having substituents in the
p-position to amine-group practically do not enter the reaction at all.
Sufficient range of recombination quantum yield change in the polymeric glasses studied (by 6
times) witnesses about high sensitivity of this process to the structure and molecular dynamics of
the local environment. The reaction only proceeds in local zones of relatively large (≥1nm) size,
as is found based on the analysis of quantum yield dependence on amine concentration. These
zones may be considered as peculiar nanoreactors. Macromolecular nanoreactors stipulate the
presence of essential magnetic-spin effects leading to a significant (by 10-20%) product
accumulation rate decrease in PVC and PS as external magnetic field is applied. However, the
overwhelming majority of RP is formed in small size zones of molecular diameter value and
represents contact RP, so processes of their evolution are not limited by spin dynamics, and the
main direction of their transformation is disproportioning with primary reagent regeneration. For
these RP magnetic-spin effects are absent.
High and durable photochemical post-effects are found to be the important feature of the process
proceeding in chlorine-containing polymers (PVC) and in PMMA and CTA films prepared by
using chlorine-containing solvent (dichloroethane). A mechanism of significant photochemical
post-effect is suggested and kinetic description is proposed. The formation of dye at irradiated
film treatment by HCl is diffusion limited. This allows to use the reactions studied in the
investigations of both slow and fast diffusion processes in polymers.
104
PHOTOSTIMULATED ELECTRON TRANSFER IN STRUCTURES
OF MUTATIONALLY MODIFIED REACTION CENTERS
FROM PHOTOSYNTHETIC BACTERIA
A.I. Kotelnikov1, E.S. Medvedev1, N.S. Goryachev1, A.V. Barinov1,
A.A. Stuchebrukhov2, J.M. Ortega3
1 - Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
2 - Department of Chemistry, University of California, Davis, CA, USA
3 - Instituto de Bioquimica Vegetal y Fotosintesis, Universidad de Seville-CSIC, Seville, Spain
kotel@icp.ac.ru
High efficiency of the photo-stimulated electron transfer (ET) reactions in biological systems
including structures of reaction centers attracts attention of numerous investigators. Analysis of
the major factors affecting the rate of such reactions is important both in the aspect of basic
knowledge and for developing artificial systems of energy storage and conversion. It has been
established that ET in biological systems occurs as a chain of successive ET events in protein
structures between either metal-containing centers or organic donor-acceptor groups over the
distances of 5-25 Å. Studies of the ET reactions in protein structures developed by Nature during
Evolution for performing this function can be much more informative than in any other
molecular or nanosystem since in proteins mutual arrangements of the donor-acceptor centers
and their environments are fully identical, the feature that is difficult to provide in artificial
molecular systems. Extensive development of biochemical and molecular genetic methods of
protein modification enables to purposely change chemical structures of donor-acceptor
complexes and their redox potentials, and to perform site-directed replacements of amino-acid
residues along the transfer path or in vicinities of donor-acceptor centers, which influences the
most of the physical factors determining the ET rate.
In a series of studies experimental and theoretical investigations have been performed of the
temperature dependence of kinetics of the photo-stimulated ET between proximal heme c-559 of
the cytochrome and the bacteriochlorophyll dimer in native and seven mutationally modified
reaction centers (RC) isolated from photosynthetic bacterium Rps. viridis, in which amino acid
tyrosine L162 located at the transfer path was replaced by phenylalanine, tryptophan, glycine,
methionine, leucine, threonine, or histidine. In frames of a new theoretical model developed on
the basis of approximations due to Ovchinnikova, Helman, Sumi and Marcus, the major factors
determining the ET kinetics in the temperature range from room to helium temperature, i.e., the
matrix element squared, the characteristic frequencies of protein reorganization, and the
reorganization energy of the matrix, have been analyzed. The times of dipole relaxation of the
matrix and the activation energy of this process have been determined. The results are compared
with the data on the protein relaxation dynamics obtained by the methods registering the
relaxation shifts of the phosphorescence and fluorescence spectra of the dyes incorporated into
the protein structures.
The work was supported by RFBR (grant 08-03-00094), the Government of Spain (BFU200768107-C02-01/BMC), NSF (PHY 0646273), and NIH (GM54052).
105
LUMINESCENCE TECHNIQUE IN THE STUDY OF BIOLOGICAL
PROPERTIES OF FULLERENE BASED HYBRID NANOSTRUCTURES
R.A. Kotelnikova1, D.V. Mishchenko1, D.A. Zhokhova1, A.V. Barinov1,
A.Yu. Rybkin1, N.S. Goryachev1, G.N. Bogdanov1, V.V. Grigoriev2,
V.S. Romanova3, A.I. Kotelnikov1
1 - Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
2 - Institute of Physiologically Active Compounds RAS, Chernogolovka, Russia
3 - Institute of Organoelement Compounds RAS, Moscow, Russia
kotel@icp.ac.ru
A wide spectrum of biological activity of fullerene derivatives (FD) allows them to be
considered as potential high active drugs treating many social diseases. An important task is a
study of molecular mechanisms of biological action of FD, their effect on structure and functions
of the most important enzymatic systems and biological membranes. These tasks are successfully
solved using fluorescent and triplet probes. Due to high phosphorescence lifetimes of triplet
excited chromophores, sensitivity of triplet probes to dynamic interactions is several orders of
magnitude higher than that of conventional fluorescence and ESR methods. It has been shown
that amino acid FD are efficient quenchers of triplet probes of eosine, erythrosine and pyrene.
Phosphorescence quenching rate constant for erythrosine and delayed annihilation fluorescence
rate constant for pyrene, which were built in liposome membranes, were determined. Both
phosphorescence and delayed fluorescence were quenched by different FD. The ability of FD to
penetrate through a lipid bilayer to the internal volume of liposomes was determined using a
triplet probe technique. To study the distribution of FD in animal organs, a luminescent hybrid
structure (HS) based on С60-proline and eosine was designed, which is now used to investigate
the mechanisms of neuroprotective action of fullerene derivatives. For HS based on Gd@C82 and
eosin, both fluorescence and phosphorescence of eosin were fully quenched probably via the
excitation or charge transfer mechanism. Since endometallofullerene-eosin bond cleavage results
in a sharp increase in fluorescence intensity, this effect provides high sensitivity and allows one
to study stability of such hybrid structures in physiological conditions. Biological activity of
different types of fullerene based HS is demonstrated on some examples.
The work was supported by the Program N27 of Presidium RAS and the Program N9 of
Department of Chemistry and Materials Science RAS.
106
PHOTONICS OF SINGLET OXYGEN DIMOLS AND MONOMOLS:
RESULTS OF PHOTOCHEMICAL AND LUMINESCENCE STUDIES
A.A. Krasnovsky
A.N. Bach Institute of Biochemistry RAS and M.V. Lomonosov Moscow State University,
Moscow, Russia
phoal@mail.ru
The ground state of oxygen molecules is triplet. Upon energy absorption, relatively low-lying
oxygen singlet states 1∆g and 1∑g+ are populated. Interaction of singlet oxygen molecules leads to
formation of singlet oxygen dimols (1O2)2. Energy of the lowest 1∆g state is about 1 eV. Energy
of the 1∑g+ state is about 1.6 eV. In dimols due to energy pooling, summation of energy of two
singlet oxygen molecules occurs. Luminescence properties of these singlet oxygen species are
well known. Absorption properties are studied much worse, because the oxygen absorption
bands corresponding to the triplet-singlet transitions are very weak and can be detected only at
very high oxygen pressure (100-150 atm.). Recently, we developed a simple photochemical
approach to investigation of the absorption bands of dissolved oxygen at normal atmospheric
pressure. This method is based on measurement of photooxygenation rates of the 1O2 traps upon
direct excitation of oxygen by IR laser radiation. Using this method, we have shown that singlet
oxygen is readily formed upon direct excitation of dissolved oxygen by laser radiation at 765,
1064 and 1270 nm in air-saturated organic solvents and aqueous detergent dispersions. The
obtained data allowed us to estimate the absorption spectra, optical densities and molar
absorption coefficients (ε) of O2 corresponding to these bands. It was shown that the intensities
of these bands are markedly different from those obtained at high pressure. Especially strong
difference was found when the 1064-nm and 1270-nm bands were compared. The data suggest
that absorption of dimols dominates in the reported high pressure spectra. This causes selective
up to ≈50-time increase of the 1064-nm band. The spectrum of photosensitized luminescence of
singlet oxygen dimols was shown to correlate with this conclusion. The molar absorption
coefficients for the 1270-nm absorption band were compared with the rate constants (kr) of the
1
O2 radiative deactivation obtained from measurement of photosensitized 1O2 phosphorescence at
1270 nm. It was found that in organic solvents the values of ε and kr correlate. However in
aqueous micellar dispersions, ε was 3-6 times higher than kr in water requires. This effect was
shown to be partially caused by higher kr and solubility of oxygen in the micellar phase. We plan
to discuss contribution to this effect of solvent OH groups and micelle charge and propose an
improved diagram of electronic transitions in dimol and monomol molecules.
Acknowledgements
This work is supported be the grants of the Russian Foundation for Basic Research and the
Programs of the Presidium of the Russian Academy of Science.
References.
1. Krasnovsky A.A., Ambartzumian R.V., Chem. Phys. Lett., 2004, 400, 531-535.
2. Krasnovsky A.A., Roumbal Ya.V., Ivanov A.V., Ambartzumian R.V. Chem. Phys. Lett.,
2006, 430, 260-264.
3. Krasnovsky A.A., I.V. Kryukov, A.V. Sharkov, Proc. SPIE, 2007, 6535, 65351Q1- Q5.
4. Krasnovsky A.A., J. Photochem. Photobiol. A: Chem. 2008, 196, 210-218.
5. Krasnovsky A.A., Ya.V. Rоumbal, A.A. Strizhakov, Chem. Phys. Lett., 2008, 458, 195-199.
107
DFT MODELLING OF ADENINE STACKING DIMERS IN WATER
I.V. Krauklis, Yu.V. Chizhov, V.L. Rapoport
St.Petersburg State University, Russia
Kraukle@yandex.ru
This work is continuation of complex researches on the luminescence and the quantum chemical
analysis of stacking aggregates of the bases of nucleic acids [1, 2]. The quantum chemical
research included modelling and DFT calculations by the method B3LYP/6-31+G(d) of
geometry and electronic characteristics of adenine tautomers (Ade7 and Ade9) and adenine
stacking dimers, consisting of Ade7 and Ade9, in aqueous solutions. The account of influence of
water solvent was made using the polarizable continuum model (PCM). All calculations were
performed with the suite of programs Gaussian03 [3] on HPC-claster at Faculty of Applied
Mathematics and Control Processes of Sankt-Petersburg State University.
Initial structures of dimers were modelled from the molecule of diadenosine monophosphate
(АрА), in which molecules of adenine are in stacking conformation with the interplane distance
R = 3.4 Å and the angle of a turn θ = 36° (see fig.1).
Ade9/Ade9
ApA
Fig.1. The scheme of modelling of adenine stacking dimer Ade9/Ade9 from the molecule АрА.
Our quantum-chemical calculations confirm existence of energetically favourable stacking
dimers of Ade in water (see table 1). All stable in aqueous solution stacking conformers of Ade7
and Ade9 have the interplanar distance R ≈ 3.42 ÷3.49 Å. The stacking dimer Ade9/Ade9 has
the greatest difference of full energy ∆Е = -0.284 eV due to connecting of two monomers. The
mixed dimers Ade9/Ade7 and Ade7/Ade9 also are stable in water: ∆Е = -0.133 eV and ∆Е =
-0.169 eV, correspondingly. Formation of staсking dimer Ade7/Ade7 is doubtful: the difference
of full energy at formation is small ∆Е = -0.041 эВ, and the interplanar distance is equal R ≈ 3.67
Å. It is known, that the percentage ratio of tautomers in a water solution makes Ade7: Ade9 =
20 %: 80 %. Therefore the probability of that 1 molecule Ade7 will contact with other molecule
Ade7 in eight times less, than probability of collision Ade7 c Ade9.
Table 1. Characteristics of stable in aqueous solution stacking dimers of Ade.
Ade9/Ade9
R ≈ 3.49 Å, θ = 36°
E = -934.748656 a.u.
d = 6.79 D
∆Е = -0.284 eV
Ade9/Ade7
R ≈ 3.46 Å, θ = 36°
E = -934.740836 a.u.
d = 14.40 D
∆Е = -0.133 eV
Ade7/Ade9
R ≈ 3.42 Å, θ = 36°
E = -934.742169 a.u.
d = 10.62 D
∆Е = -0.169 eV
Ade7/Ade7
R ≈ 3.67 Å, θ = 36°
E = -934.735030 a.u.
d = 21.05 D
∆Е = -0.041 eV
[1] Rapoport, V.L., Malkin, V.M. et al. // Doklady Akademii Nauk, 2006, Vol. 406, No. 3, pp.
402-406.
[2] Krauklis I.V., Chizhov Yu.V., and Rapoport, V.L. // The monography “Self-organizing of
complex molecules”, under edition prof. Korotkov V.I., St.Petersburg State University, 2008,
pp. 128-140.
[3] Gaussian 03, Revision B.05, Frisch M.J., et al. Gaussian, Inc., Pittsburgh PA, 2003.
108
MODELING OF EVOLUTIONARY PRIMITIVE ENERGY CONVERTER
AND MOLECULAR DEVICES BASED ON THE ACTIVITY
OF PHOTOEXCITED FLAVINS
M.S. Kritsky
A.N.Bach Institute of Biochemistry RAS, Moscow, Russia
mkritsky@inbi.ras.ru
The modeling of biomolecular processes is widely used in analysis of problems of prebiotic
evolution and in the design of nanodevices. The present lecture overviews the models based on
the activity of isoalloxazine derivatives, flavins, the compounds acting as coenzymes in “dark”
biocatalysis and, besides, playing role of photon sensors in proteins. Their excited molecules
function in flavoprotein photoenzyme DNA-photolyase as well as in photoregulators of living
activities, cryptochromes and LOV- and BLUF-domain containing proteins. When excited,
flavin chromophore initiates electron transfer reactions in protein, which lead to catalytic act in
photolyase or, in photoregulator proteins, these reactions cause conformational changes in
polypeptide thus activating its effector domain. Both electron transfer and the signal transduction
cascade are of interest in view of modeling.
The experiments mimicking physicochemical conditions of prebiotic Earth have demonstrated
abiotic formation and functioning of polymolecular systems consisting of flavoproteinoid
pigment molecules aggregated in aqueous medium to form phase separated microspheres. These
microspheres are capable to utilize photon energy by converting it into the energy of chemical
bonds. Under the influence of short wave visible and the UV-A radiation, isoalloxazinecontaining pigment in microspheres sensitizes formation of energy-rich phosphoanhydride bonds
in ATP. The phosphorylation mechanism involving free radical reactions of isoalloxazine and
ADP has no analogs in modern organisms. Despite its high efficiency (the yield of ATP per ADP
mol reached 35 %), such systems could not compete photosynthesis for a role of global converter
of solar energy in biosphere, first of all, because of a one order of magnitude lower photon
absorptivity of isoalloxazines as compared to porphyrins.
In modern biosphere photochemical activity of flavins remained in photoproteins which are
involved in adaptation of organisms to environment. These photoactive flavoproteins as well as
artificial complexes of flavins with redox proteins are prototypes of molecular devices such as
the systems with photocontrolled electron conductivity. Flavin photocatalyst combined with a
high potential electron donor is capable to perform a strictly light-dependent injection of electron
into redox protein molecule such as multihaem cytochrome, which haem groups differ in their
electrode potential values.
Supported by Basic Research Program No 15 of the Presidium of Russian Academy of Sciences
and grant No 07-04-00460_а from Russian Foundation for Basic Research.
109
ENERGY TRANSFER IN THE MOLECULAR SYSTEMS
NEAR DIELECTRIC AND METAL SURFACES
M.G. Kucherenko, T.M. Chmereva, D.A. Kislov
Orenburg State University, Russia
rphys@mail.osu.ru
The electron excitation energy transfer between adsorbed molecules on a solid surface via virtual
and real surface excitons is considered. The rate of energy transfer via virtual excitons is
calculated analytically. The nonradiative energy transfer to surface impurity centers is
considered in the case of rapid migration of 2d-virtual or real excitons leading to repeatedly
changed distances between centers of excitation localization. A theoretical model of the kinetics
of “surface exciton-T-center” cross annihilation is constructed as a mirror image of the theory of
cross annihilation of oxygen- containing objects adapted to a system of quasiparticles.
The radiationless energy transfer of the electronic excitation between molecules adsorbed by flat
side of a conductor is investigated. It is shown, that the energy transfer with participation of
surface plasmons can be the effective mechanism in such system. The distance and angular
dependence of the energy transfer rate in the donor-acceptor pair of adsorbates are obtained.
Comparative estimates of efficiencies of a direct dipole-dipole and plasmonic channels of energy
transfer are yielded. The dominating (exceeding on 2-3 orders of transfer rate in the system
without conductors) contribution of the plasmonic mechanism in general energy transfer rate
between donor and acceptor molecules near the metal surface is found. However, at zd and
za ≈ R , where R - intermolecular distance, efficiencies of distance and plasmonic mechanisms
of the energy transfer become comparable on quantity. At the further removal of molecules from
a surface of conductor zd and za >> R the distance mechanism becomes prevailing, and
surface influence is insignificant.
Properties of surface plasmons change essential at transition to small metal particles. Analytical
expressions for composite matrix elements of the donor-acceptor dipole-dipole interaction,
including intermediate plasmonic states are obtained. Estimates of an intermolecular energy
transfer rate in the presence of metal nanoparticles are yielded in the approximation of dipole
plasma oscillations. The similarity of total expressions for transfer rates are found in the cases of
conductor flat side and metal nanoparticle. The yielded estimates of expected effect quantities
are used for the preparation of the experimental observation of inductive-resonant energy
transfer between organic dye molecules in the metal nanoparticle colloidal solutions.
This work was supported by the Russian Foundation for Basic Research (project no. 08-0299035- r2006_ofi) and the Ministry of Education and Science of the Russian Federation (under
assignment no. 1.3.06 from the Federal Agency of Education).
1. Kucherenko M. G., Chmereva T.M. Exciton Energy Transfer between Adsorbates
// Physics of the Solid State. 2008. vol. 50. №3. p.531-537.
2. Chmereva T.M., Kucherenko M.G. Plasmon Energy Transfer between Adsorbates // JTP
Letters (to be published).
110
COOPERATIVE PROCESSES OF ANTI-STOCKES
LUMINESCENCE EXCITATION IN CRYSTALS
WITH ADSORBED ORGANIC DYE MOLECULES
N.V. Kvashnina, O.V. Ovtchinnikov, A.N. Latyshev, A.F. Klinskikh,
M.S. Smirnov, T.I. Suvorova
Voronezh State University, Russia
opt@phys.vsu.ru
Among low-threshold two-quantum processes of exitation of anti-Stockes luminescence
processes of sensibilised by organic dye molecules anti-Stockes luminescence (SASL) in AgHal
crystals, exited by light streams 10-5–10-9 Vt/сm2 take important place. This phenomenon was
explained by V.V. Ovsjankin and F.F. Feofilov alike exitation of SASL in rear earth elements
within the bounds of cooperative scheme of adding exitation energy in adsorbed organic dye
molecules. But there are still no unique proves of this mechanism and there is no full physical
scheme of energy upconversion.
In this paper results of investigation of this effect in AgCl, AgCl(I), Zn0.6Cd0.4S crystalls
containing adsorbed organic dye molecules of: methylene blue, 1,1’-diethyl-2,2’-hinocianin and
3,3’-di-(γ-sulfopropil) – 9-ethyl-4,5-benzo4’,5’-[4”5”-dimethileno(2”3”)]-tiatiazolocarbocianinbethaine salt; malachite green are introduced. Samples were both microcrystal poweders and
optically homogeneous gelatine matrixcies, containig layers of nanorocrystals.
Most important legitimacies are the following: 1) SASL exitation spectrums have the same peak
as absorbtion spectrums of monomeres, J-, H-aggregates of organic dyes 2) Hypsochromic shift
takes place in case of H-aggregates of organic dyes on the surface of crystals, batochromic shift
takes place in case of J-aggregates 3) concentration dependences of peak intensities meaning
processes of organic dye molecules aggregation has threshold type – and starts with monomeres
concentration, wich is characterised by distances between geometric centeres of molecules about
50–150 Å – by order of Ferster‘s radius 4) with decreasing of average distances between
adsorbed molecules up to 45–15 Å aggregation possibility increases and there is alike
concentration dependences of SASL intensities 5) creation of energy states of adsorbed atomes
and clusters of metal destroys most of theese legitimacies.
The above mentioned legitimacies allowes us to tend to cooperative
process of adding of energy of two quantums of simultaneously
excited dye molecules. So, the most possible is transfer to crystall of
electron exitation energy of two molecules, cumulated in one of
them. The adding mechanism could be different from the classical
induct-resonance transfer with the fact that irradiate transfer is
possible at a point of crossing of system (A*+A*) and (A+A**)
terms and goes on like predissosiation prosess.
This work is supported by RFFI grant (№08-02-00744).
111
THE ROLE OF INTRINSIC POINT DEFECTS IN SPECTRAL SELFSENSITIZATION OF WIDE-BANDGAP OXIDE PHOTOCATALYSTS
A.A. Lisachenko
St.Petersburg State University, Russia
lisachen@photonics.phys.spbu.ru
In 1930 years professor Terenin has started the pioneering research on photophysics and
photochemistry of adsorbed molecules. Terenin discovered the photoactivated dissociation of
adsorbed molecules under UV-irradiation of wide-bandgap oxides. Of special importance was
that the spectral region of active light exceeds the bounds of fundamental absorption of
nominally pure oxides as well as that of the molecule. Thus only the intrinsic defects (lowcoordinated ions, defects in the crystal lattice) might cause the light absorption. This work has
been started under his supervision and is followed up to now in his laboratory in the Physical
Institute of Leningrad (St.Petersburg) University. Some results of this work are discussed in the
present report.
In nominally pure oxides light absorption in the region 1 < hν <6 eV may be caused by numerous
point defects of varied nature. However the defects of F-type (an oxygen vacancy which
captured one or two electrons) and those of V-type (a metal vacancy which captured one or two
holes) are of special interest because of their capability to transform the light energy into the
chemical one.
Various complementary experimental methods such as: mass-spectrometry, thermodesorption
spectroscopy, optical (diffusion reflectance), photoluminescence and electron spin resonance
spectroscopies, as well as UV (8.43 eV) photoelectron spectroscopy, have been adapted to carry
out in situ investigations in three phases: gas, adsorbate and solid state. Single crystals and
dispersed powders of nominally pure oxides were irradiated by monochromatic light with the
power of 10−3 to 10−1 W/cm2 in the UHV ~10−9 Torr or in a flow of pure gases (H2,O2, CO, NxOy)
under a controllable pressure of ~10−8÷10−1 Torr.
The primary steps of electron subsystem excitation are the spectral-selective and site-sensitive
excitations of point defects accompanied by a charge transfer between the excited states and the
valence or the conduction.bands, and terminated by a chemical bonds breaking or/and bonds
rearrangements on the surface.
Highly active oxygen species are created at a photoactivated oxide surface, allowing
to oxidize a
+
number of adsorbed molecules. We have demonstrated that point defects of F, F and V-type can
be used for self-sensitization of photocatalysts to a sub-bandgap spectral range on an example of
a lot of gas-wide bandgap oxide systems including NOx/Al2O3 and (NO + CO)/TiO2 systems.
The most effective self-sensitization is reached when nanosized 2D-heterostructures are created
on the surfaces of photoreduced TiO2 and ZnO.
This work was supported by RFBR under grant 09-03-00795-a
112
TRIPLET ENERGY TRANSFER FROM d0 ORGANOMETALLICS
TO UNSATURATED HYDROCARBONS:
RECENT RESULTS AND PERSPECTIVES
G.V. Loukova, V.A. Smirnov
Institute of Problems of Chemical Physics RAS
gloukova@mail.ru
Triplet – triplet energy transfer (TET) is the most common and important type of energy transfer involved
in chemical and biochemical processes. It is known that electron-exchange (Dexter) resonant energy
transfer mechanism, responsible for “physical” emission quenching, requires orbital overlap between
energy donor and acceptor molecules which is also essential for formation of chemical bonds and can be
associated with chemical interactions. Notably, systematic studies of the relationship between the rate
constant (effectiveness) of electron-exchange resonant energy transfer and chemical interactions appear to
be scarce.
Recently, we initiated [1] a systematic study of photophysics of d0 group IV metallocenes, possessing rare
highly emissive (for Cp2MCl2 where Cp = C5H5–, M = Zr and Hf: ΦLUM = 1 at 77K), extremely long-lived
(τ in the range of milliseconds at 77 K) ligand-to-metal charge transfer excited states excited states. In this
account, we discuss results of our on-going study of electron-exchange resonant energy transfer between
d0 organometallic complexes based on Zr(IV) and Hf(IV) as the highly-emissive (phosphorescent) energy
donors and unsaturated hydrocarbons (UHC) as the non-phosphorescent energy acceptors, having lowlying triplet state (ЕТ ~ 25000 cm–1), in organic media. In these systems, chromophores Cp2MCl2 (M = Zr,
Hf) can be selectively excited. After intersystem crossing with 100 % efficiency, the long-lived state
energy of the metal complexes is transferred to UHC, resulting in emission quenching of the metallocene
(the efficiency of intermolecular triplet energy transfer was examined by steady-state emission at 77 K). It
was established that concentration dependences of the emission quenching efficiency obey the Perrin
equation, attributed to electron-exchange resonant mechanism of interaction. It is revealed that
arrangement of an unsaturated quencher around a d0 metal complex affects the observed resonant energy
transfer efficiency and coordinative interaction. As a principle effect, on the basis of our TET data, we
reveal the existence of significant coordinative interaction between the title d0 organometallic complexes
and olefins (dienes) and estimate distances at which d0 metallocene – UHC orbital interactions,
responsible for electron-exchange energy transfer and inner- and outer-sphere coordination, are effective.
The inner-sphere coordinative structures between the energy donors and acceptors, suggested in our TET
study, are also revealed by means of density functional theory and ab initio calculations [2]. Steric
hindrance and coordination are proposed to account, for instance, for the lack of the phosphorescence
quenching with 3,3-dimethylbutene-1 as a low-lying (ЕТ ~ 25000 cm–1) triplet energy trap. Notably, the
approach enables studying homogeneous systems with very low – catalytic concentrations of metal
complexes (c ≤ 10–4 mol/l) which cannot be achieved by any other conventional physico-chemical
methods. Solvent effects on orbital interaction between d0 bent metallocenes and dienes will be for the
first time discussed in view of microscopic (structural), rather then macroscopic bulk (polarity, etc.)
properties of solvent molecules.
These findings provide a new example of TET use for studying intermolecular interactions, in particular,
the first example of systematic study of coordination between unsaturated hydrocarbons and d0 πcomplexes by the energy transfer approach. The organometallic reactions have proven difficult to be
studied by direct measurements, evaluation of rate constants being a historical quest. Accordingly, such a
photophysical approach may be promising in the mechanistic study of key stage of organometallic
polymerization catalysis: the in situ formation of cationic catalytic species, coordination and following
insertion of substrate molecules.
Acknowledgement. The authors gratefully acknowledge Professor A.E. Shilov for stimulating discussion
and RFBR (grant N 09-03-00379) and RAS for financial support.
References
[1]. G.V. Loukova, S.E. Starodubova, V.A. Smirnov, J.Phys.Chem. A. 2007, 111, 10928; G. V. Loukova,
V. A. Smirnov, Chem. Phys. Lett. 2000, 329, 437; G. V. Loukova, Chem. Phys. Lett. 2002, 353, 244.
[2]. G.V. Loukova, A.A. Milov, V.A. Smirnov, 2009, submitted.
113
SENSIBILIZED ANTI-STOCKES LUMINESCENCE MECHANISM
IN CRYSTALLS WITH ADSORBED METALORGANIC
NANOSTRUCTURES
O.V. Ovtchinnikov, T.I. Suvorova, N.V. Kvashnina, M.S. Smirnov,
A.N. Latyshev, D.A. Minakov, V.A. Shulgin
Voronezh state university, Russia
opt@phys.vsu.ru
In variety of investigations an effect of sensibilised anti-Stockes luminescence (SASL) intensity
enhancement in AgHal-crystals and solid solutions of Zn0.6Cd0.4S with adsorbed organic dye
molecules caused by creation of small atomic Ag-clusters on the surface both caused by lowtemperature photostimulated process (LTPSP) and adsorbtion from solution was found. It was
shown, that the SASL excitation center consists of adsorbed organic dye molecule and a Agcluster, and exitation has two-quantum type. But the abcense of data about interaction type
between components of the SASL exitation center doesn’t let find a final exitation mechanism of
this radiation.
In this paper the results of experiments on space parting of Ag-claster and organic dye molecules
adsorbed to AgCl(I) by a gelatine layer is introduced. The equipment consists of standart optical
connector and two quarz fibres. Laser radiation KLM-H-650-40-5 (λmax=650 nm, Pmax = 40 mVt)
were submit to input wave guide. Radiation flow was 1020quantum/(с*сm2) at output of first
wave guide. Sample was put into an optical connector between input and output wave guides.
Radiation was detected by PEE -79 with optical filter BGB-22.
Legitimacies of SUCL intensity of exhibition time, 77K, λ=650nm, Р=5mVt, 1- AgCl(I) crystalls,
2- AgCl(I) crystalls and gelatine layer with MB; and with Ag-clasters, created during synthesis:
3 - AgCl(I) crystalls, 4- AgCl(I) crystalls and gelatine layer with MB
SASL value of pure crystals could be explained by adsorbed Ag-clasters of biography nature.
SASL intensity changed unmonotoneously during exhibition of sample with pure crystals and
sample consisting of two gelatine layers – one with methylene blue (MB) molecules, second with
AgCl(I) crystals. SASL intensity of an integrate sample is higher than one without organic dye
molecules. Sensibilization of SASL radiation by LTPSP products started earlier and went faster
for an integrate sample than for pure crystals. For long exhibition times SASL attained
saturation, then decay part was observed. It was confirmed for AgCl(I) crystals, the surface of
which had a significant concentration of Ag-clusters during synthesis. Finally, SASL excitation
center consists of adsorbed organic dye molecule and a Ag-cluster. Bind between them is weak,
but it is enough for electron excitation energy transfer from organic dye molecules to Ag-cluster
and for its following photoionization. The gelatine molecule interferes electron transfer.
114
LUMINESCENCE STUDY OF STABLE STACKING AGGREGATES
OF NITRIC BASES OF NUCLEIC ACIDS – THE CANDIDATES
FOR ROLE OF FIRST GENETIC TEMPLATES
V.L. Rapoport, V.M. Malkin, I.V. Krauklis, E.A. Maslova, V.V. Goriuchko
V.A. Fock Institute of Physics, St.Petersburg State University, Russia
victor.rapoport@paloma.spbu.ru
It is generally believed that the world of RNA was preceded by simpler organic replicative
systems. The nature of RNA precursors remains unknown.
By luminescence spectroscopy methods we have revealed stable stacking dimers and other
stacking aggregates of nitric bases of nucleic acids in water which may be interpreted as
precursors of RNA molecules in chemical evolution (proto-RNA) and first genetic templates [1,
2]. Their luminescence spectra have maxima at 400–600 nm and excitation spectra have exciton
splitting 3000–4000 cm-1.
It was shown that stacking dimers don’t dissociate even at 85ºC. This unusual stability may be
explained by ions and water bridges between two molecules in dimer. The propose about ion
bridges was confirmed by the quantum chemistry calculations (DFT/B3LYP method) of the
system: stacking dimer of adenine and 2-3 Na+ ions which gave stabilization energy ~ 2 eV.
Replication mechanism of stable stacking aggregates without any ferments based on consecutive
rises and falls of temperature (1–25 ºC) is discussed [1]. It consists of two phases. At low
temperature (1–4 ºC) a new stacking dimer, e.g. of adenine, is formed from two monomers on
stacking dimer of uracyl (thymine). At temperature rise to 25ºC the two stacking dimers sever
one from another and a new stacking dimer of adenine appears in solution.
This mechanism of replication of stable stacking dimers and other aggregates was confirmed in
luminescence study of mixed water solutions of adenine and uracyl (thymine). At cooling of
adenine+uracyl mixed solutions from 40 to 1 ºC the anomalous fall of luminescence intensity of
adenine stacking aggregates was observed, that was explained by forming of H-bond between
adenine and uracyl. At temperature rise from 1 to 40 ºC for the same mixed solution the
anomalous rise of luminescence intensity of adenine stacking aggregates was observed due to
dissociation of H-bonds.
At cyclic temperature rises and falls (4–40 ºC) of adenine+uracyl mixed solution the rise of
luminescence intensity level of adenine stacking aggregates at 4ºC was observed that confirms
the proposed replication mechanism of stable stacking aggregates of nitric bases.
1. V.L. Rapoport, V.M. Malkin, S.V. Zorina, S.M. Komarov, V.V. Goryuchko. Luminescence
detection of tightly bound stacking aggregates of adenine and adenosine in aqueous solutions –
the candidates for the role of the first genetic templates. Dokl. Akad. Nauk, 2006, Vol. 406, No.
3, pp. 402-406.
2. V.L. Rapoport, V.M. Malkin, N.A. Bykov, V.V. Goryuchko. Origin and evolution of
biosphere. Edited by Acad. E.M. Galimov. Moscow, 2008, pp. 169–178.
This study was fulfilled at financial support of Program no.18 of Presidium of RAS.
115
FTIR STUDY OF POROUS ICE FILMS
A.V. Rudakova, I.L. Marinov, A.A. Tsyganenko
V.A. Fock Institute of Physics, St.Petersburg State University, Russia
arudakova@mail.ru
Processes on icy particles attract much attention due to importance for atmospheric science,
ecology and astrophysics. In this work, adsorption and reactions of some molecules on pure and
mixed water icy films have been investigated by means of FTIR spectroscopy.
The cell for spectral studies of adsorbed molecules at variable temperatures (55-370 K)1 was
equipped with a device for water vapour sputtering from the heated capillaries and deposition
onto the inner ZnSe windows of the cell, cooled by liquid nitrogen. Lower temperatures were
obtained by pumping off evaporating nitrogen from the coolant volume.
The estimated specific surface area of freshly deposited at 77 K water ice film was about 160
m2/g and decreases on raising the temperature together with the diminishing intensity of the
bands of dangling OH (OD) groups at 3696 (2727) cm-1 until the latter disappear at 130 – 160 K
when the changes of bulk absorption provide evidence for a phase transition from amorphous to
polycrystalline ice. CO adsorption at 77 K results in two bands at 2153 and 2137 cm-1 assigned
to molecules forming weak H-bond with the dangling hydroxyl groups or bound to unsaturated
surface oxygen atoms, respectively2. The band of dangling hydroxyl groups moves to lower
wavenumbers at adsorption of different molecules (hydrogen, nitrogen, methane, ozone, NO,
ethane or chlorinated ethenes, etc.) Besides this shift, spectra of adsorbed N2, CO and methane
registered at 55 K reveal absorption intensity decrease at ~ 2650 cm-1 at the high-frequency slope
of bulk absorption, and increase at about 25 cm-1 below. This new effect we interpret as a
strengthening of H-bonds between surface water molecules, which act as adsorption sites either
as proton-donor or as a donor of the lone pair of electrons.
Spectra HCN/D2O and ND3/D2O mixed icy films with low (1:10) dopant/water ratios do not
manifest any changes in the acidic or basic properties of dangling hydroxyl groups or surface
oxygen atoms, but reveal a difference in the proportion between concentrations of these sites
comparing with pure water ice. For high dopant concentrations (1:1) the dangling hydroxyls
were not observed, the dominant adsorption sites for CO are likely to be the unsaturated oxygen
atoms, while serious structural changes occur in the bulk of ices.
Ecologically important reactions like ozonolysis of chlorinated ethenes or hydrogen cyanide at
77 – 200 K, as well as the influence of UV radiation on this process have been studied. Ozone
co-adsorption with C2H3Cl at 77 K readily leads to ozonolysis reaction, while for the C2H2Cl2
isomers it starts only at 120–150 К. Ozone co-adsorption with HCN in the dark does not lead to
any noticeable spectral changes. However, UV irradiation of this system results in the
appearance of new bands revealing the formation of ozonolysis products. Spectral dependence of
photo-ozonolysis of HCN at 77 K has shown that photodissociation of ozone, evidently, accounts
for the observed process.
The above results, thus, show that the surface of ice particles plays the role of a condenser of
atmospheric pollutants and acts as a micro-photoreactor in the atmosphere.
Acknowledgments.
The work was supported by INTAS (grant 03-51-5698) and RFBR (06-03-32836a).
1. Otero Areán С., et al. Eur. J. Inorg. Chem. 2001. No 7. 1739.
2. Rudakova A.V., et al. Langmuir. 2009. V. 25. № 3. P. 1482-1487.
116
THE PRODUCTS AND MECHANISMS OF PHOTOCHEMICAL
TRANSFORMATION OF O-QUINONES
M.P. Shurygina, Yu.A. Kurskii, N.O. Druzhkov, S.A. Chesnokov, G.A. Abakumov
G.A. Razuvaev Institute of Organometallic Chemistry RAS, Nizhnii Novgorod, Russia
sch@iomc.ras.ru
It is known that o-quinones undergo various photochemical transformations upon irradiation
which have theoretical and important practical interest. In this work we report about systematic
investigation of kinetics and products of photodecarbonylation of o-benzoquinones (DBQ) and
photoreduction of DBQ and 9,10-phenantrenequinone (PQ) in the presence of different
hydrogen donors (DH).
The kinetics and products of photodecarbonylation of the series of 4,5-di-substituted 3,6-di-tertbutyl-o-benzoquinones upon irradiation by visible light (λ>520 nm) was investigated. NMR
monitoring of photolysis of quinones detected that it is a two-stage process. On the first stage the
photoexcited molecule of quinone rearranges into bicyclo-compound containing three- and fivemembered cycles which spontaneously decomposes during the following dark stage into 3,4disubstituted 2,5-di-tert-butyl-cyclopentadienon and a molecule of CO.
O
R
hν
R
O
O
- CO
O
R
O
The kinetics and products of photoreduction of the series of 4-substituted 3,6-di-tert-butyl-obenzoquinones and PQ in the presence of para-substituted N,N-dimethylanilines and
polymethylbenzenes upon irradiation with light λ>500 nm was investigated too. It was
established that photoreduction of both o-benzoquinones and 9,10-phenantrenequinone occurs
through common mechanism of products formation. NMR-monitoring detected that first stage of
process is formation of product with uniform structure (I) – corresponding phenolether.
O
R
+ DH
O
OH
hυ
R
O D
I
OH
D ; D
OH
;
R
OH
II
R
O
III
It was discovered that stability of phenolethers is determined by both redox characteristics and
structure of o-quinone and H-donor. Phenolethers formed in the reaction with DBQ decompose
through heterolysis mechanism into corresponding catecholes (II) and different amines during
dark reaction. The phenolethers which were formed by photoreaction of PQ with N,Ndimethylanilines undergo rearrangement to give corresponding ketols (III) during dark process.
Phenolethers – derivatives of PQ and polymethylbenzenes convert only under irradiation and in
the presence of second molecule of PQ to form ketols.
Acknowledgments: This work was supported by the Russian Foundation for Basic Research
(grant no 07-03-00711, 08-03-12090-ofi, 08-03-97055-r_povolzj’ye_a) and Russian President
Grant supporting Scientific Schools (NSh-4182.2008.3).
117
MESO-SUBSTITUTED POLYMETHINE DYES AS EFFICIENT
SPECTRAL-FLUORESCENT PROBES FOR BIOMACROMOLECULES
A.S. Tatikolov, T.M. Akimkin, A.S. Kashin
N.M. Emanuel Institute of Biochemical Physics RAS, Moscow, Russia
tatikolov@sky.chph.ras.ru
A search of simple and convenient methods for the study of biological objects, in particular, the
use of dye probes, is of importance for investigative and experimental purposes. Our task is to
find dyes that can serve as spectral-fluorescent probes for various biomacromolecules in the
analysis and the study of biological systems. Meso- (or 9-) substituted polymethine dyes can
serves as such probes. For unsubstituted polymethine dyes the cis-isomer usually has higher
energy than the trans-isomer, and the trans-cis equilibrium is shifted toward the trans-isomer.
For meso-substituted polymethine dyes the energies of the trans- and cis-isomers can be
comparable due to steric hindrances, the trans-cis equilibrium becomes movable and is shifted
toward one or another side depending of the medium. This makes meso-substituted polymethine
dyes promising for application as spectral-fluorescent probes for biomacromolecules. We used
one of such dyes, 3,3’-di(sulfopropyl)-4,5,4’,5’-dibenzo-9-ethylthiacarbocyanine betaine, whose
interaction with biomolecules we studied earlier [1, 2], as a probe for analysis of the extracellular
media of the human eye and the eye of some animals for albumin and collagens. We also studied
the interaction of the other meso-substituted polymethine dye, 3,3’-di(sulfopropyl)-9methylthiacarbocyanine betaine, with human and bovine serum albumins and showed that this
dye can serve as a spectral-fluorescent probe for serum albumins. We studied the noncovalent
interaction of a number of squarylium dyes (which can be considered as polymehtine dyes with a
meso-substituent) with serum albumins of various animals and found that one of these dyes can
also serve as a probe for serum albumins. The interaction of 3,3’,9-trimethylthiacarbocyanine
with DNA was studied by us in detail; it was shown that the dye forms with DNA fluorescent
complexes of two types: intercalation and minor groove complexes. The binding constants and
the binding numbers were determined for both types of the complexes. It was also found that the
dye interacts with hyaluronic acid to form H-aggregates on its molecules.
Thus, meso-substituted polymethine dyes can serve as efficient spectral-fluorescent probes for
various biomacromolecules in studies of biological objects.
The work was supported by the Russian Foundation for Basic Research (project 09-04-01054a).
References:
1. A.S. Tatikolov, S.M.B. Costa. Complexation of polymethine dyes with human serum
albumin: a spectroscopic study. Biophys. Chem. 2004. V. 152. P. 33–49.
2. A.S. Tatikolov, I.G. Panova. A spectroscopic study on the interaction of polymethine
dyes with collagens. High Energy Chem. 2005. V. 39. No. 4. P. 232–236.
118
PHOTOACTIVATED TEMPLATES
IN PREBIOTIC EVOLUTION PROCESSES
T.A. Telegina, M.P. Kolesnikov, Yu.L. Vechtomova, M.S. Kritsky
A.N. Bach Institute of Biochemistry RAS, Moscow, Russia
telegina@inbi.ras.ru
According to present views, numerous processes in prebiotic evolution were mediated by
mineral and organic templates. These templates ensured local concentration and spatial
orientation of reactive molecules, isolate them from aqueous environment and also perform
catalytic function. The templates themselves were subjected to evolution, which finally led to
formation of a perfect mechanism based on self-replicating polynucleotides, which direct a
structure of protein catalysts. The template-mediated processes were a source of ATP and other
chemically activated nucleotide derivatives for early metabolism, and transformation of free
energy in these systems is a important aspect of their evolution.
The main way of energy supply for abiogenic template syntheses of organic matter was a direct
activation of their reaction centers by heat and solar light. Mineral templates can drive lightdependent processes, which result in a formation of molecules of various level of complexity.
We have shown that mineral templates containing semiconductor metal oxides (TiO2, Fe2O3,
etc.), when subjected to UV-irradiation were capable to photoreduce molecular nitrogen to
ammonia and, in presence of acetaldehyde, sensitize a formation of amino acids – glycine,
alanine and serine. The energized particles of clay mineral, montmorillonite, were shown to
catalyze formation of pyrophosphate and phosphoanhydride bonds in nucleotide coenzymes ATP
and FAD.
Complication of organic molecules in process of chemical evolution was accompanied by coevolution of the templates driving transformation of these molecules. According to our data, the
UV-irradiated aqueous solution of acetaldehyde and ammonium nitrate accumulated amino
acids, pyruvic acid and indoles, and, besides, melanoidin structures. The presence of these
structures, in turn, had ensured that amino acids condensed in water environment and formed
peptides. In addition, melanoidin templates demonstrated catalytic activities mimicking the
activity of some redox enzymes (alcohol dehydrogenase, lactate dehydrogenase).
Transition from mineral templates to organic matrixes has expanded their capacities as
photosensitizers and permitted chemical evolution to utilize solar photons of visible area for a
synthesis of chemically activated metabolites. Thermolysis of amino acids mixtures results in a
formation of abiogenic pigmented polymers (flavoproteinoids), which aggregate to form
microspheres. These flavin-containing structures were shown to conserve energy of photons of
both blue and the UV area into the energy-rich bonds of ATP. The yield of ATP reached 30 %
per mol of ADP and the quantum efficiency of the process was ca. 20%.
Some functions of canonic templates could be mimicked in chemical evolution by
physicochemical situations formally not falling into a category of templates, but still manifesting
some their properties. For instance, highly concentrated solutions and the melts of organic
molecules, mimick the concentration effect and ensure water-free conditions of templates. As an
example, abiogenic formation of AMP from aspartate, glutamine, glycine, formate, carbonate
and orthophosphate in ribose melt will be discussed.
Supported by Basic Research Program No 15 of the Presidium of Russian Academy of Sciences
and grant No 07-04-00460_а from Russian Foundation for Basic Research.
119
ADVANCES IN SPECTRAL STUDIES OF SURFACE PHENOMENA
A.A. Tsyganenko
V.A. Fock Institute of Physics, St.Petersburg State University, Russia
tsyg@photonics.phys.spbu.ru
The paper deals with the advances of FTIR spectroscopy for the studies of lateral interaction
between adsorbed molecules, changes of site strength caused by the interactions, linkage
isomerism of surface species and explanation of the above phenomena in the electrostatic
approach.
The strength of sites depends dramatically on surface coverage. Strong repulsive inter-action on
oxides can stop adsorption when only a part of sites are occupied1. The observed strength of acid
sites diminishes due to the static effect, whose mechanism includes relaxation induced by
adsorption2, while the dynamic coupling shifts the bands and changes their shapes. Coadsorption of weak acids with basic molecules demonstrates the effect of induced Bronsted
acidity3, when the presence of SO2 or NO2 leads to protonation of bases (NH3, pyridine or 2,5dimethylpyridine) even on silica, Increase of electron-accepting properties of surface cations
caused by adsorbed acids, as well as basicity induced by co-adsorbed bases were also detected4.
Spectroscopy at variable temperatures broadens the list of molecules used for acid site testing,
which includes now CO, NO or H2 that do not adsorb at 300 K. Low-temperature adsorption of
weak CH proton-donating molecules such as acetylene, CHF3, HCN enables one to characterize
the strength of surface electron-donating sites. Recently it was shown that CO reveals linkage
isomerism and forms with surface cations both C-bonded and O-bonded complexes. The latter
has the frequency lowered with respect to the gas phase5 and coexists in thermodynamic
equilibrium with the usual C-bonded form. Having the energy considerably higher, this form of
adsorption can be considered as “sterically activated” state, which could act as intermediate in
catalytic reactions6. Surface isomeric states were established for some other adsorbed species, such
as cyanide ion CN- produced by HCN dissociation.
The existence of linkage isomerism can be explained by a simple electrostatic model7. Besides
the linear configurations with positively charged sites, the model predicts formation of side-on
complexes of CO and N2 with surface anions8. Strong interaction of CO with the most basic
oxygen sites of a number of oxides leads finally to the formation of ‘carbonite’ CO22- ion9.
Spectra evolution with temperature provides information on the mechanism of surface reactions
illustrated by CO or thiophene-d2 isotopic scrambling over CaO10.
Quantitative analysis of adsorption sites needs the knowledge of absorption coefficients. Both
quantum chemistry and electrostatic approach predict the correlation between the frequency
shifts on adsorption and the integrated absorption coefficients. For CO the latter decreases when
the frequency grows on interaction with the cations, but increases for O-bonded species with
lowered C-O stretching frequency, in a fair agreement with the theory11.
References:
[1] Tsyganenko A.A., Denisenko L.A., Zverev S.M., Filimonov V.N. J.Catalysis, 94 (1985), 10.
[2] Tsyganenko A.A., Zverev S.M. React. Kinet. Catal. Lett., 36 (1988), 269.
[3] Tsyganenko A.A., et al. Catal. Letters, 70 (2000), 159.
[4] Storozheva E.N., Sekushin V.N., Tsyganenko A.A. Catal.Letters. 107 (2006), 185.
[5] Otero Areán C., Turnes Palomino G., Tsyganenko A.A., Garrone E. Intern. J.Mol.Sci., 3 (2002), 764.
[6] Tsyganenko A.A., Storozhev P.Yu., Otero Areán C. Kinet. Catalysis, 45 (2004), 530.
[7] Storozhev P.Yu., et al. Appl. Surface Sci., 238 (2004), 390.
[8] Tsyganenko A.A., Kondratieva E.V., Yanko V.S., Storozhev P.Yu. J. Mater. Chem., 16 (2006), 2358.
[9] Babaeva M.A., Bystrov D.S., Kovalgin A.Yu., Tsyganenko A.A. J. Catal. 123 (1990), 396.
[10] Tsyganenko A.A., Can F., Maugé F. J. Phys. Chem. B, 107 (2003), 8578.
[11] Kondratieva E.V., Manoilova O.V., Tsyganenko A.A. Kinetics and Catalysis, 49 (2008), 451.
120
POSTERS
BACTERIORHODOPSIN-CONTAINING MULTILAYER STRUCTURES
AS A MEDIUM FOR BIOMOLECULAR NEURONET DEVICES
OF PHOTONICS
G.E. Adamov, D.A. Adamova, E.P. Grebennikov, V.R. Kurbangaleev
OJSC CSRIT Technomash, Russian Federation, Moscow
ntc_technology@socket.ru
Due to constant development of nanotechnologies and functional nanomaterials used in
information systems researchers need to look for new ideas and radically new constructive
solutions to ensure efficient device operation, record-breaking high speed and integration of
elements. On the other hand, functional elements being formed in nanometer range require
landmark approaches. It refers especially to formation of information-logical devices at
molecular level.
The techno-systematic problem is the necessity to use “macro-nano” and “nano-macro”
interfaces to put in the original information and deduce final results. The advantages of the
small-size molecular elements can’t help to ensure access to them. Probably the only effective
way to arrange the bonding with molecular system is to use optical interaction. The solution
seems to be connected with hierarchic structural and functional self-organization of molecular
systems that is with using assemblies of molecules as a basis of molecular information-logical
appliances.
The techno-systematic approaches aimed at implementation of biomolecular neural network
appliances based on multilayer polymeric photochromic structure are detailed to describe.
Mentioned below biological material – Bacteriorhodopsin protein – has unique technological
potential and its optical properties allow the use of optical input-output devices and create
molecular appliances based on self- organization principles.
The optimization and enhancement of functional parameters of multilayer structures by, first,
using additional nanostructuring of molecular media, and, second, by introduction of new
functional elements – hybrid nanostructures (making it possible to further realize a new class of
optical information systems based on self-organizing oscillatory and auto wave hierarchical
processes in BR-containing nanocomposites) are suggested.
121
PROTONATION EFFECT AND SPECTRAL PROPERTIES
OF PHOTOCHROMIC COMPOUNDS
A.O. Ait, V.A. Barachevsky, A.M. Gorelik, O.I. Kobeleva
Photochemistry Center RAS, Moscow, Russia
ait@photonics.ru
The hypsochromic shift for solutions of spiropyranes and spirooxazines in comparison with
chromen’s batochromic shift under irradiate of UV light in presence of protonic acid will be
discussed. The influence of subtitutes on spectral properties has been investegated.
For example, the solution of 3,3-diphenyl-3H-naphto[2,1-b]pyran in acetonitril under UV
irradiation in absence of acid has λ max 435 nm and λ max 610 nm in presence of perchloric acid
(Fig. 1). The solution of 1`,3`-dihydro-1`-phenyl-3`,3`-dimethyl-6-nitro-8-methoxyspyro[2H-1benzopyran-2,2`-(2Н)-indole] (Fig.2) has opposite effect - λ max 580 nm and 420 nm accordingly.
Fig.1. Absorption spectra of solution of 3,3-diphenyl3H-naphto[2,1-b]pyran in acetonitril under UV
irradiation in absence of acid (1) and in presence (2)
of perchloric acid
Fig.2. Absorption spectra of solution of `,3`-dihydro-1`phenyl-3`,3`-dimethyl-6-nitro-8-methoxyspyro[2H-1benzopyran-2,2`-(2Н)-indole] under UV irradiation in
absence of acid (1) and in presence (2) of perchloric
acid
The accomplished molecular modeling with using of semi-empirical quantum-chemical methods
showed that such shifts of the absorption bands are connected with the various length of the
conjugated chain of the protonic and unprotonic forms for chromenes, on the one hand, and
spiropyranes and spirooxazines on the other.
122
SPECTRAL-FLUORESCENT STUDY OF THE INTERACTION OF
THE POLYMETHINE DYE CY2 WITH DNA AND HYALURONIC ACID
T.M. Akimkin1, A.S. Tatikolov1, S.M. Yarmoluk2
1 – N.M. Emanuel Institute of Biochemical Physics RAS, Moscow, Russia
2 - Institute of Molecular Biology and Genetics NASU, Kyiv, Ukraine
tatikolov@sky.chph.ras.ru
Recently a number of works concerning polymethine (cyanine) dyes have covered the studies of
their noncovalent interaction with DNA and proteins. In those works it was suggested to use
some polymethine dyes as fluorescent probes for biopolymers. In our work we studied the
interaction of one of such dyes, 3,3’,9-trimethylthiacarbocyanine (Cy2), with DNA. Combined
measurements of the absorption and fluorescence spectra of the Cy2–DNA system were
performed within a wide range of DNA concentrations. The growth of the dye fluorescence
quantum yield caused by the increase of the DNA concentration in the solution was simulated
mathematically. While simulating, we assumed two types of dye–DNA binding: intercalation
and minor groove binding. The binding constant and the binding number were determined by
computer fitting of the experimental data with a simulation curve.
The interaction of Cy2 with hyaluronic acid is also studied in this work. Hyaluronic acid is a
basic component of the extracellular matrix of organisms, such as synovial fluid, liquid media of
the eye etc.; therefore, a search of dye probes for hyaluronic acid is of current importance. We
measured the absorption spectra of Cy2 in the presence of hyaluronic acid at different pH of the
medium. As the hyaluronic acid concentration increased, we observed an appearance of shortwavelength bands in the absorption spectrum and a growth of their intensity, due to the
formation of H-aggregates of Cy2 on hyaluronic acid molecules. Using the decomposition of the
absorption spectra into several Gauss components, we studied changes in the intensities of the
separate bands of the aggregates as the hyaluronic acid concentration increased. We concluded
that Cy2 can serve as a spectral probe not only for DNA, but also for hyaluronic acid in
biological systems.
The work was supported by the Russian Foundation for Basic Research (project 09-04-01054a).
123
DFT SIMULATION OF PHOTOCATALYTIC NO REDUCTION
BY СО ON Ti8O16 NANOCLUSTER
A.S. Andreev, Yu.V. Chizhov
V.A. Fock Institute of Physics, St.Petersburg State University, Russia
yurichizhov@yandex.ru
Titanium dioxide is well known as one of the best photocatalyst to decompose many of the
environmentally hazardous substances. Many photocatalytic properties of titanium dioxide are
related to the existence of surface oxygen vacancy (surface F-centers). We regard (TiO2)n
clusters as a model of that isolated structured defects on surface TiO2 bulk. In this work, the
simulation of the catalytic reaction 2NO + 2CO → N2 + 2CO2 (1) on the stable full optimized
Ti8O16 cluster was performed.
The calculations were done using the DFT method with B3PW91 functional. Hay and Wadt
pseudopontential for Ti atoms was used and for light atoms was applied 6-31G basis.
The simulation of reaction (1) was carried out in a few steps:
Ti7O15-Ti4+O → Ti7O15-Ti3+ + O(3P)
(2a)
Ti7O15-Ti4+O + CO → Ti7O15-Ti3+-OCO
(2b)
3+
4+
Ti7O15-Ti + 2NO → Ti7O15-Ti O2N2
(3)
Ti7O15- Ti4+O2N2 + CO → Ti7O15-Ti4+O + N2↑ + CO2
(4)
An oxygen vacancy can be obtained due to direct removal the oxygen atom (2a) or interaction
with CO (2b).
Reaction (2a): According to the calculations for the removal of oxygen atom is necessary to
expend 5.96 eV of energy. As a result reduced cluster Ti7O15-Ti3+ is created. The electronic
structure of optimized Ti7O15-Ti3+ shows well developed band structure with single electronic
band gap defect state strongly localized on Ti3+.
Reaction (2b): Adsorption of CO on the Ti4+O leads to the formation of adsorption complex
Ti7O15-Ti3+-OCO with bond-lengths R(Ti3+-O) = 2.13 A, R(O-CO) = 1.192 A, R(OC-O) = 1.170
A, what indicates the formation a CO2 molecule. Energy of CO2 desorption is 0.94 eV, i.e. in
order to take a reduced Ti7O15-Ti3+ cluster during the reaction (2b) is necessary an additional
energy to expend. According to the experimental work [1] CO2 was desorbed upon heating the
TiO2 sample.
Reaction (3): Adsorption of 2 molecules of NO on the Ti3+ leads to the formation of the stable
adsorption complex Ti7O15-Ti4+O2N2 with bond-lengths R(Ti4+-O) = 1.88 A, R(N-O) = 1.41 A,
R (N-N) = 1.27 A in the symmetric planar chelate cycle Ti4+O2N2. The N-O bonds are strongly
weakened as compared with free NO molecule.
Reaction (4) is a key reaction. Calculations showed that the approach of a CO molecule to the
adsorption complex Ti7O15-Ti4+O2N2 leads to formation free N2 molecule and weakly adsorbed
CO2 molecule with a desorption energy of 0.27 eV. The reaction takes place with release of 4.57
eV of energy. After desorption of CO2 titanium dioxide cluster returns to its original oxidized
Ti7O15-Ti4+O form, thus the catalytic cycle of reaction (1) is closed.
Thus the reaction of catalytic NO reduction by CO on Ti8O16 nanocluster may take place in 3
phases. It appears that the photoexcitation is necessary only in the reactions (2a) and (2b), in
which costs of energy is required. The all main results of the calculations are in agreement with
experimental data [1].
[1] Andrei A. Lisachenko, Ruslan V. Mikhailov, Lev L. Basov, Boris N. Shelimov and Michel
Che, Photocatalytic Reduction of NO by CO on Titanium Dioxide under Visible Light
Irradiation, J.Phys. Chem. C, 2007, 111(39), 14440-14447
124
RELAXATION OF HIGH-LYING EXITED ELECTRONIC STATES
OF POLYPYRIDYL RU(II) COMPLEXES AND ITS RELATION TO
SYMMETRY OF MOLECULAR STRUCTURE AND/OR ENVIRONMENT
E.S. Artemyeva, S.V. Litke
V.A. Fock Institute of Physics, St.Petersburg State University, Russia
SVLitke@yandex.ru
Polypyridyl ruthenium(II) complexes are of great interest in the study of exited state redox and
sensitization processes due to the low-lying metal-to-ligand charge transfer (MLCT) exited states
with high luminescence efficiency and long lifetimes. Owing to these properties the complexes
have many applications in such fields as luminescent sensors, photocatalysis, light-emitting
diodes (LEDs), photovoltaic devices and so on. Photochemical stability of polypyridyl Ru(II)
complexes depend on location of metal-based 3dd – states whose population result in weakening
of metal – ligand bond down to ligand loss. A process of thermal excitation of 3dd – states from
low-lying 3MLCT – state(s) at elevated temperatures is at present the commonly accepted model.
We assume that another path of 3dd – states population exists along with thermal excitation,
namely, a direct population of the states during relaxation of high-lying exited electronic states
of complexes. In the course of this study homo- and heteroleptic mononuclear ruthenium(II)
complexes have been investigated in solution and in adsorbed state by optical absorption and
luminescent spectroscopy. Absorption, excitation luminescence and diffuse scattering spectra, as
well as luminescence quantum yields under UV and Vis excitation were measured. It was found
that absorption and excitation luminescence (active absorption) spectra of homoleptic complexes
in solution were coincided to one another for the most part whereas those of heteroleptic
complexes were different. Also the differences of the spectra were revealed for homoleptic
complexes adsorbed on a surface of amorphous silica i.e. in heterogeneous environment. These
observations were confirmed by measurements of luminescence quantum yields of the
complexes under excitation in UV absorption band near 290 nm (caused by intraligand, IL
transitions) and in Vis absorption band near 450 nm (caused by MLCT transitions). The probable
mechanism of 3dd – states population and its relation to symmetry of complexes and/or
environment are discussed.
125
2D-STRUCTURE EVIDENCE ON THE SURFACE
OF SELF-SENSITIZED ZnO PHOTOCATALYST
L.L. Basov, A.A. Lisachenko
V.A. Fock Institute of Physics, St.Petersburg State University, Russia
lisachen@photonics.phys.spbu.ru
ZnO is one of widely used photocatalysts in environmental catalysis. While the value of its
bandgap is as high as 3.2 eV and the fundamental absorption lies in UV it exhibits high
photocatalytical activity in visible region.
The charge transfer theory of photocatalysis considers the photoactivated system as being a
three-dimensional one. Electron-hole pairs created during the band-to-band transitions,
photoionisation of impurities or structural defects are extracted to the surface. The energy
transfer distance is of the order of diffusion length. In such model the photocatalytical activity
depend on crystal electrophysical parameters - Fermi level, surface band bending, work function.
In another limiting case the effect is considered to be connected with the local surface centers.
The excitation in this case includes a charge transfer inside the surface structure. The effect
depends only slightly on surface potential value (if at all).
A lot of complementary experimental methods such as: mass-spectrometry, thermodesorption
spectroscopy, optical (diffusion reflectance), photoluminescence and electron spin resonance
spectroscopies, as well as UV (8.43 eV) photoelectron spectroscopy, contact potential difference,
photoelectromotive force have been adapted to carry out in situ investigations in three phases:
gas, adsorbate and solid state.
The failure of the charge transfer three-dimensional model has been suggested.
Indeed,
1) a spectral maximum of photocatalysis was observed in the spectral region of sub-bandgap
absorption, the value of the initial quantum yield can approach to 1.0;
2) a "memory effect" (relaxation times up to 104 s) was found in photoactivated processes;
3) the illumination in the spectral region of sub-bandgap absorption is not accompanied by a
surface charge transfer into the bulk;
4) the adsorption of molecules of the gas phase is not accompanied by an observable change of
the surface potential;
5) the intensity of the photoeffect and even its sign (photoadsorption ↔ photodesorption) can be
changed when very little number of surface local centers was created without shifting the Fermi
level nor the band bending value.
Thus, the density of surface centers is rather high, they interact between themselves, but their
interaction with the bulk of the crystal is weak and the system can be considered as a twodimensional one.
This work was supported by RFBR under grant 09-03-00795-a
126
PHOTOPHYSICAL PROCESSES IN CATIONS
OF THIACARBOCYANINE DIMERS
O.K. Bazyl, V.Ya. Artyukhov, G.V. Mayer
Tomsk State University, Russia
okbazyl@rambler.ru
The excited electronic states and rate constants of photophysical processes in thiacarbocyanine
cation dimers (D13) are calculated by the semiempirical method of intermediate neglect of the
differential overlap with special spectroscopic parameterization [1]. A “sandwich” structure with a
parallel (D13-1) and an antiparallel (D13-2) orientation of the short axes of the molecules
forming a dimer is worked out. The spacing between the molecular planes in the dimer is taken
to be 3.5 Å. The results of calculations are compared with the experimental data on dimers in [2].
The dimer conformations D13-1 and D13-2 produce similar spectra. Analysis of the nature of
MO forming the S1 and S2 dimer states and comparison of their nature with that of the S1
monomer state show that the first two electron states in dimers are a split S1 monomer state. In
so doing, the electron transition to the S1(ππ*) state from the ground one becomes either
forbidden (D13-1) or weakly allowed (D13-2), with the intensity of the second transition of the
dimer being much higher than that of the first transition in the monomer. According to the
calculation, the intensity of the long-wavelength band in dimers forms the S0→ S2(ππ*) transition
whose energy and intensity are higher than those of the S0→S1(ππ*) transition forming a longwavelength band in the monomer absorption spectrum. The experimentally observed maximum
of the long-wavelength dimer absorption band [2] is close to the energy of the calculated S0→
S2(ππ*) transition.
According to the data reported in [2], thiacarbocyanine dimers exhibit low fluorescence an it is
masked by the monomer fluorescence of higher intensity, the quantum yield of dimer
fluorescence ranges between 0.021 and 0. 0003, and low radiation capacity is believed to be due
to forbiddenness of the radiative transition and high efficiency of the ST-conversion in dimers as
compared with monomers. The calculations of rate constants of photophysical processes in
dimers show that the formation of dimers significantly affects the energy level diagram of the
excited electronic states of the monomer. In dimers with parallel and antiparallel arrangements of
the short axes of its constituent molecules, the rate constant of the radiative decay of the
fluorescent state (kr) is decreased by a factor of 2-4 depending on the orientation of dimer
molecules relative to each other.
As for the efficiency of the processes of internal (kic) conversion and singlet-triplet (kST)
intersystem crossing, both nonradiative processes show a two-threefold increase in the efficiency
at the most. However, despite such a pronounced increase in the efficiency of the singlet-triplet
crossing, this nonradiative process in D13-1 and D13-2 dimers is less efficient than the radiative
decay and internal conversion, and affects the quantum fluorescence yield but slightly. In so
doing, the value of the rate constant of these nonradiative processes depends on the dimer
structure. Internal conversion is the process suppressing fluorescence in D13-1 and D13-2
dimers, which lends no support to the assumption [2] of a significant quantum yield of
intersystem crossing in dimers as compared with monomers.
The calculations show that the ST-conversion in dimers is 2-3 orders of magnitude higher than
that in monomers, yet, this nonradiative process will not be determining in the fluorescence
quenching (kr ≈ 104 - 106, kic ≈ 108 - 109, kST ≈ 104 - 106 s -1).
References
1. V. Ya. Artyukhov and A. I. Galeeva. Izv. Vyssh.Uchebn. Zaved., Fiz.. 1986. №11. P. 96.
2. A. K. Chibisov. Khim. Vys. Energ. 2007. V.41. No. 3. P. 239.
127
THE STRUCTURE AND PHOTOPHYSICAL PROCESSES
IN SYMMETRIC POLYMETHINE DYES
O.K. Bazyl1, V.Ya. Artyukhov1, V.A. Svetlichnyi1, A.A. Ishchenko2
1 - Tomsk State University, Russia
2 - Institute of Organic Chemistry NAS, Ukraine
okbazyl@rambler.ru
Polymethine dyes (PDs), owing to a great variety of their spectral-luminescent prorerties, are
widely used in various fields of science and engineering. For a targeted search for PDs with
desired properties, it is necessary to know relations between their electronic structure and
intramolecular photophysical processes of deactivation of the energy excited electronic states.
However, such processes have not yet been studied theoretically based on quantum-chemical
calculations. The quantum-chemical semiempirical method of intermediate neglect of differential
overlap with special parametrization were calculated the electronic structure, energies of exited
electronic states and the rate constants of photophysical processes in isolated the cationics of
molecules of vinylogous series of indocarbocyanine 1-5.
H3C
CH3
N
BF4
CH3
CH3
H3C
n
N
CH3
Figure. Structural formulas of symmetric cationic indopolycarbocyanine dyes 1-5:
n=1(PD1), 2 (PD 2), 3 (PD 3), 4 (PD 4) and 5 (PD 5).
Influence of structural factors (length of polymethine chain (PC), output from the molecular
plane the PC carbon atoms or the end fragments (EFs)) was investigated on the rate constants of
photophysical processes. The calculations show, what the lengthening PC in the polymethine
series of 1-5 leades to decrease the radiative decay rate constant ( kr) of a fluorescent state less
than twofold. A more pronounced decrease in kr occurs with displacement of EFs or PC carbon
atoms from the molecular plane. However, in these cases, kr also decreases only by several times
rather than by an order of magnitude. The lengthening PC in the polymethine series of 1-5
decreased the S1→S0 transition energy, this the internal conversion rate constant (kic) increases
by almost two orders of magnitude. The magnitude of kic is nearly independent of the
displacement of individual atoms or fragments from the chromophore plane. The calculation of
the singlet-triplet crossing rate constant (kST ) show that the appreciable deactivation of a
fluorescent state along the this channel take place only if the planarity of the molecule is
disturbed. However, the rate constant kST be little even if its structure is nonplanar, which agrees
well with experimentally data. With increasing PC length on efficiency of singlet-triplet crossing
begin iflyencend the interaction between the fluorescent state and the T2(ππ*)state, spin-orbit
interaction with which is appreciable more than with T1(ππ*) state.
The analysis of efficiency of photophysical processes and the calculation of the quantum yields
of the fluorescence show, that intramolecular photophysical processes cannot be responsible for
the difference between the calculated and measured fluorescence quantum yield in the
polymethine of 1- 5. Under the experimental conditions, these molecules must have additional
channels of the fluorescent state degradation. The comparison of the calculated and measured
fluorescence quantum yields allow suppose that most probably, the main processes competing
with the fluorescence of PDs are the photoisomerization for PD 1 and the energy transfer to the
oxygen singlet (or solvent) for PDs 4 and PDs 5. In molecules 2 and 3 processes of deactivation
on named channels are minimum.
This study was supported by the Russian Foundation for Basic Research (project no. 07-02-00155-a).
128
SHORT AND LONG-RANGE ORDER EFFECT
ON RESONANCE ENERGY TRANSFER
E.N. Bodunov
Physics Department of St.Petersburg State Transport University, Russia
evgeny.bodunov@inbox.ru
The theory of luminescence quenching in fluids and solids due to resonance energy transfer
(RET) from energy donors (excited molecules) to energy acceptors (quenchers), starting with the
pioneering studies by Förster and Dexter, is based on the assumption that molecules are point
particles homogeneously distributed in the medium. In this case, the radial distribution function
of molecules g(r) does not depend on the distance r between the particles and is equal to unity
for 0 < r < ∞, i.e., quenchers are homogeneously and independently distributed around an
excited molecule. In later investigations, a distance of closest approach was introduced, and the
radial distribution function was modeled by the unit step function. In fact, the radial distribution
function is more complicated function of distance than step function. In crystals, there is a longrange order. On the other hand, in liquid and molecular glasses, and even in the absence of
coulomb or van der Waals potential, a short-range order exists owing simply to the finite size of
the molecules, and the radial distribution function has the shape of damped oscillations. In this
report, the luminescence decay law resulting from quenching by RET is investigated and the
hard-sphere fluid model is used to take into account the short-range order of media. In polar
media, donors and acceptors can exist as cations and anions. Therefore, the long-range coulomb
interactions (electrostatic repulsion and attraction of donors and acceptors) are also taken into
account.
129
THE LIQUID CRYSTAL COMPOSITES CONTAINING
AN IMPURITY OF FLUORESCENT CdSe NANORODS
V.V. Danilov1, A.V. Baranov2, G.K. Elyashevich3, A.O. Orlova2,
N.A. Utkina1, A.I. Khrebtov1
1 - Research Corporation “S.I. Vavilov State Optical Institute”, St.Petersburg, Russia
2 - St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
3 - Institute of Macromolecular Compounds RAS, St.Petersburg, Russia
vdanilov@hotbox.ru
For the first time the fluorescence of quantum rods (QRs) CdSe in liquid crystal (LC) composites
on the basis of cyanobiphenyls is investigated. As one would expect, the fluorescence of QRs
CdSe in LC cells is strongly polarized, however the degree of polarization has the negative value
connected with volumetric orientation QRs. Obviously, this orientation is also responsible for the
lower absolute values of the degree of polarization in the QRs band in comparison with the
degree of polarization of the matrix fluorescence. The found effect of solubilizer molecules on
the orientation of s opens new possibilities for developing controlled multilayer LC cells.
For the first time are received LC composites containing QR CdSe on the basis of nanostructered
porous polythene films. The presented spectral data testify to a high degree of polarization of QR
fluorescence, which speaks about alignment properties of stretched polythene films. Introduction
the impurity LC composites in porous polymer allows to reduce sharply coagulation of rods
CdSe
130
INVESTIGATION OF SPECTRAL PROPERTIES OF ISOXAZOLE
DERIVATIVES CONTAINED PHOTOCHROMIC LABEL
O.V. Demina1, A.V. Laptev2, N.E. Belikov2, A.Yu. Lukin2,
R.V. Zemtsov2, S.D. Varfolomeev1, A.A. Khodonov2
1 - N.M. Emanuel Institute of Biochemical Physics RAS, Moscow, Russia
2 - M.V. Lomonosov State Academy of Fine Chemical Technology, Moscow, Russia
ovd@sky.chph.ras.ru
The investigation of the regulation of ligand–receptor or ligand–enzyme interactions by the
usage of organic compounds with photochromic labels on the subcellular or molecular levels is
one of the significant tasks of bionanophotonics and nanomedicine. The search of new effective
variants of the direct regulation of the human hemostasis system definite stages is the important
medicine problem, because the mortality from cardio-vascular diseases takes first place in the
world.
It was shown by us that a number of 3,5-substituted isoxazoles were potent anti-aggregatory
compounds [1,2]. A few 3,5-substituted isoxazole analogs (1,2) contained photochromic label spiropyran moiety at 3-position of isoxazole ring were synthesized by us for the determination of
molecule pharmacophoric fragment detail structure and the investigation of the action
mechanism of this class compounds. Photochromic properties of synthesized compounds were
investigated by spectral-kinetic methods.
O
N
R
NO2
N
O
(1) R= CH2OH
(2) R= C6H5
This work was partly supported by RFBR grants (projects № 09-04-01003 and 09-03-00565).
References
1. O.V. Demina, A.A. Khodonov, V.I. Shvets, S.D. Varfolomeev. Aggregation of human
platelets: molecular – kinetic mechanisms and the paths of their regulation. // Biological
membranes (Rus.) (2002), 10(2), pp. 115-152.
2. O.V. Demina, P.V. Vrzhesch, A.A. Khodonov, V.I. Kozlovsky, S.D. Varfolomeev. Synthesis
of new inhibitors of platelet aggregation – substituted pyridyl isoxazoles and their 4,5-dihydro
analogs. // Bioorganic Chem. (Rus.) (1995), 21(12), pp. 933-940.
131
HETEROGENEOUS PHOTOCATALYSIS BY ZINС PHTHALOCYANINE
DERIVATIVES FOR PHENOLS OXIDATION
T.M. Fedorova, E.G. Petrova, V.M. Derkacheva, A.V. Butenin, O.L. Kaliya
Organic Intermediates and Dyes Institute, Moscow, Russia
fedorova-tm@yandex.ru
Water-soluble and immobilized on Amberlite IRA 400 phthalocyanine derivatives are known to
be active sensitizers for phenol and chlorophenols phototransformation by singlet oxygen [1] as
well as for photodynamic therapy of cancer [2]. We had used substituted PcZn for
photooxidation of 1,5-dihydroxynaphthalene to 5-hydroxy-1,4-naphthoquinone (juglone) [3].
Heterogeneous photosensitizers have some advantages over the soluble ones. They are more
stable in many cases, can easily be separated from reaction solution and reused.
The preliminary results of phenol photooxidation by dioxygen in alkaline solution in the
presence of substituted PcZn immobilized on carrier by equilibrium adsorption are presented in
this report. The adsorption isotherm has been received and treated in coordinates BET.
Photochemical oxidation was carried out in the glass reactor surrounded by a water jacket (to
keep the content cool) at permanent stirring and dioxygen bubbling through the mixture. The
visible light source was a 150 W halogen lamp with cutoff filter to remove irradiation with
wavelenghts less than 450 nm. The reaction was monitored by reverse phase HPLC. It has been
found that phenol conversion is influenced by the nature of carrier (SiO2, modified SiO2, Al2O3,
Amberlite) and substituents (PhS, PhSO2, t-Bu) in PcZn molecule as well as by the amount of
immobilized PcZn. Phenol conversion has run 95% in 120 min irradiation for the most active
heterogeneous photocatalyst. The last one was stable during six cycles. As expected phenol
photooxidation efficacy has been increased in D2O (lifetime 1O2 in D2O more than in H2O) and
decreased in NaN3 (physical quencher of 1O2) solution. These experiments demonstrate that
singlet oxygen is involved in the photoreaction.
Quantum yield for phenol oxidation (φPhOH) and quantum yield of 1O2 with heterogeneous and
homogeneous photosensitizer (φ∆) have been determined with using laser as irradiation source
(671 nm). The value of φPhOH has been calculated from the initial linear part of the kinetic curve
phenol expenditure at initial [PhOH]=5·10-4M in according to the known relationship [4]. The
relative method with known sensitizers as reference and chemical trap was used to estimate φ∆
[4].
References
1. Wöhrle D., Kaneko M., Nagai K., Gerdes R., Suvorova O. (2008) Environmental
cleaning by molecular photocatalysis (in Molecular Catalysis for Energy Conversion,
Eds. T. Okada, M. Kaneko), Springer Series in Material Science, 263-298.
2. Kaliya O., Lukyanets E., Vorozhtsov G. (1999). Catalysis and photocatalysis by
phthalocyanines for technology, ecology and medicine, Journal of Porphyrins and
Phthalocyanines, 3, 592-610.
3. The method of 5-hydroxy-1,4-naphthoquinone preparation. Inventors certificate USSR
1559649 (1987).
4. Ozoemena K., Kuznetsova N., Nyokong T. (2001). Photosensitized transformation of 4chlorophenol in the presence of aggregated and non-aggregated metallophthalocyanines,
Journal of Photochemistry and Photobiology, 139, 217-224.
132
SPECTRAL-LUMINESCENT AND LASING PROPERTIES
OF THE SOME SUBSTITUTED OF COUMARIN
R.M. Gadirov, T.N. Kopylova, L.G. Samsonova, S.Yu. Nikonov, A.G. Logis
Tomsk State University, Russia
grm882@kvadro.net
The substituted coumarins are used as laser dyes in the blue-green spectral range. In addition,
these compounds have also found application in industry, medicine, biochemistry and other
fields of science and engineering. First of all such variety in application are explained by their
spectral-luminescent properties. The derivatives of 7-aminocoumarin are wide studied because
their high quantum yields and lasing ability, but substituted 7-hydroxicoumarines are still little
studied.
In present work we present the results of experimental and theoretical studies of two coumarin
derivatives:
ether
of
furoic
acid
and
3-(4-(benzo[1,3]dioxolyl-5)thiazolyl-2)-7hydroxycoumarine (I) and 3-methylthiazolyl-7-hydroxycoumarine (II). The interest to these
compounds is aroused by that fact that compound II has high fluorescence quantum yield but it
lasing ability is low because of strong absorption from excited triplet states which lies in
fluorescence spectral range. We used this compound as test object in numerical simulation of the
generation dynamics. Compound I has similar structure and differs by substitute in thiazolyl
fragment. But the spectral-luminescent properties of these compounds very different. Compound
I has low quiantum yield in polar solvents, but at temperature of liquid nitrogen the building-up
of fluorescence is observed.
Quantum-chemical investigation show that the reason of such behavior of compound II may be
out of plain of whole substituent in 3-rd position.
133
NEW RADICAL MECHANISM OF PORPHYRIN PHOTOSENSITIZED
DESTRUCTION OF BIOLOGICAL MEMBRANES
V.V. Gurinovich1, A.V. Vorobey2, M.P. Tsvirko3
1 - Department of Physics, Belarussian State University, Minsk, Belarus
2 - Institute of Biophysics and Cell Engineering NAS, Minsk, Belarus
3 - National SRC for Ozone Monitoring, Belarussian State University,
Minsk, Belarus
gurinovich@bsu.by
The opportunity of formation the photochemical generator of cytotoxic radicals in biological
membranes was investigated. Such generator is based on electron transfer from excited
porphyrin molecule to halogenmethan when both molecules are injected into membrane. Zinc
complexes of porphyrins possessing relatively low oxidation potentials – hydrophobic Zntetraphenilporphyn
(Zn-TPP)
and
positively
charged
Zn-5,10,15,20-tetrakis(4-Nmethylpyridyl)porphyrin (Zn-TMPP) were used as photosensitizers, carbon tetrachloride (CCl4)
and bromoform (CHBr3) – as acceptors. Cytotoxicity of radicals formed was estimated by lipid
peroxidation and destruction in protein tryptophanyls of isolated erythrocyte membranes.
Photoinduced reactions were investigated immediately after model irradiation by visible light
(halogen lamp, 150 W). Destruction of tryptophanyls of membrane proteins and porphyrin
sensitizers included in membranes was registered by chromophores fluorescence. Upon
illumination of membranes containing porphyrins by visible light, tryptophanyls destruction and
photooxidation of lipids photosensitized by porphyrins are observed. In the presence of CCl4 or
CHBr3 the yield of photosensitized tryptophanyls destruction increases approximately twice.
Halogenmethans also drastically (approximately 7 times for Zn-TMPP and twice for Zn-TPP)
increase a photosensitized lipid peroxidation. Experiments with a singlet oxygen quencher –
sodium azide have shown, that azide in concentration 2 mM reduce (2,5 times) an efficiency of
tryptophanyls photodestruction in the absence of halogenmethans. At the same time azide does
not render inhibiting influence on tryptophanyls photodestruction and lipid peroxidation at
presence of CCl4. It evidence that photosensitized by halogenmethans destruction of membrane
components proceed without participation of singlet oxygen. It is essential that photodestruction
of tryptophanyls sensitized by Zn-TMPP is noticeably greater than that sensitized by Zn-TPP. At
the same time photosensitized by Zn-TMPP lipid peroxidation approximately three times less
than in case of Zn-TPP. These results match with representation that Zn-TPP is localized
preferentially in lipid bilayer while Zn-TMPP – close to membrane protein. This implies that the
destructive activity of radicals formed, as well as singlet oxygen has the expressed local
character, i.e. these radicals are highly reactionable. The data obtained evidence about an
opportunity of formation of donor-acceptor systems in cellular membranes on the basis of
porphyrins and halogenmethans, realizing photoinduced electron transfer from singlet-excited
sensitizer molecules to acceptor molecules. Halogenmethan radicals formed exhibit high
effectiveness in destruction effect on main membrane components – proteins and lipids.
134
METHOD OF NONDESTRUCTIVE READ-OUT OF INFORMATION
K. Japaridze, L. Devadze, D. Maisuradze, N. Sepashvili
Institute of Cybernetics, Tbilisi, Georgia
devadze2005@yahoo.com
The serious factor limiting an opportunity of application of spiropyrans as switches and
environments of record and storing of information in molecular computers, is destruction of
photochromic material at multiple record and partial deleting at reading the information. Process
of record is a transformation from one to the second thermodynamical stable state. Reading is
based on definition of spectral characteristics. At reading, i.e. definition in a maximum of optical
density of absorption band, there is a partial deleting of the written down information.
The purpose of the presented work is attempt to prevent destruction during record and partial
deleting at reading the information.
To avoid deleting of the information at record, usually it is possible by means of matrixes where
photochromic transformation is accompanied by changes which can be detected without
destruction of the written down information.
In our case such environment had appeared liquid-crystalline smectogenic mixture of cholesteryl
oleate and cholesteryl pelargonate with definite ratio. The composition consists of liquidcrystalline matrix and spiropyran as dopant (1-4% by weight). The system is characterized by a
red shift of Bragg reflection i.e. dλ/dt < 0. Under certain conditions, near transition temperature
in a smectic phase («the boundary state»), dλ/dt changes a sign (hysochromic shift), half-width
of a corresponding band is narrowed and sharply intensity increases.
Fig1. Temperature dependence of Bragg reflection band at formation of "a boundary state".
(D – an apparent optical density): (1-3) cholesteric phase, (3-8) formation of "a boundary state"
(t = (1) 31, (2) 30, and (3-8) 29°C).
We assume that in a liquid-crystalline composition at presence of molecules of spiropyran с
there is a special organization of system. At photoinduction, change of geometrical
characteristics of a molecule influences on the organization of system, that in turn is exhibited in
reflection. Wavelength at which «the boundary state» is formed depends on concentration of
spiropyran. The decreasing of concentration causes bathochromic shift of band.
Therefore, reading by means of Bragg reflection band, instead of in a maximum of absorption,
will provide preservation of the written down information without loss.
135
INVESTIGATION OF THE PHOTOCHROMIC BEHAVIOUR
OF THE RETINAL PROTEIN CHROMOPHORE MODELS
A.A. Khodonov1, A.V. Laptev1, A.Yu. Lukin1, N.E. Belikov1,
R.V. Zemtsov1, K.V. Zvezdin1, V.I. Shvets1,
V.A. Barachevsky2, S.D. Varfolomeev3, O.V. Demina3
1 - M.V. Lomonosov State Academy of Fine Chemical Technology, Moscow, Russia
2 - Photochemistry Center RAS, Moscow, Russia
3 - N.M. Emanuel Institute of Biochemical Physics RAS, Moscow, Russia
khodretinal@sky.chph.ras.ru
Retinoids (vitamin A derivatives) play a key role in the functional processes in the natural lighttransforming systems based on retinal proteins – bacteriorhodopsin, halorhodopsin, visual
rhodopsin, sensoric rhodopsin, retinochrome and other. The isomerisation of definite double
bond takes place during light quantum absorption, and this act initiates cascade of events, which
is necessary for the generation of definite type physiological or chemical signals.
Nowadays, bacteriorhodopsin is one of the simplest, well-known light-converter systems. This
membrane protein was discovered in Halobacterium salinarum in 1971, and it functions as a
light-driven proton pump. The polypeptide part (bacterioopsin) consists of a sole peptide chain,
and the chromophore group is a protonated Schiff base of retinal with ε-amino group Lys-216.
Our approach to the retinal proteins structure-function investigation includes replacement of the
natural chromophore (retinal) by its analogs and complex study of their properties [1].
We proposed an effective synthetic route for the preparation of new retinal protein chromophore
models - polyenic compounds related to Vitamin A aldehyde (retinal) (1). These polyenes (2-5)
possess photochromic fragment – diarylethene or spiropyran moiety instead of the
trimethylcyclohexenic ring in its molecule. The key steps of proposed synthetic route involved
the Horner-Emmons olefination procedure of carbonyl precursor with the usage of С5phosphonate and reduction of intermediate nitrile to the polyenal by DIBAL.
Spectral and photochemical properties for the new retinal analogs in solution are discussed.
CHO
1
F
F
F
F
F
F
F
F
F
CHO
F F
S
3
F
S
CHO
S
2
OHC
S
N O
OHC
NO2
4
5
N O
NO2
This work was partly supported by RFBR grants (projects № 09-03-00565 and 09-04-01003).
References
1) Khodonov, A.A.; Eremin, S.V.; Lokshin, J.L.; Shvets, V.I.; Demina, O.V.; Khitrina, L.V.;
A.D. Kaulen, Bioorg. Khim. (Rus), 1996, 22, N10-11, 745-776.
136
INTERACTION OF CYCLOTETRAPYRROL COMPOUNDS
WITH NANOPOROUS XEROGELS AND OPTICAL RADIATION
OF DIFFERENT INTENSITY
R.T. Kuznetsova1, E.G. Ermolina1, E.N. Telminov1, G.V. Mayer1, S.M. Arabei2,
T.A. Pavich3, K.N. Solovyov3, I.P. Kalashnikova4, S.S. Ivanova5
1 - Tomsk State University, Russia
2 - Belorussian State Agricultural Technical University
3 - B.I. Stepanov Physics Institute NAS, Minsk, Belarus
4 - Institute of Physiological Active Compounds RAS, Chernogolovka, Russia
5 - Ivanovo State University of Chemical Technology, Russia
kuznetrt@phys.tsu.ru
The task-oriented applications of organic molecules and their complexes with metals on the
modern technologies for creation of different optical devices: sensors, nonlinear switches and
limiters of power pulse radiation, solid electroluminescent layers and solar concentrators [1]
demand of researches of correlations of optical characteristics with molecular structure and solid
matrices architecture where organic molecules are incorporated.
The features of interactions of tetrapyrroles with surface of pinholes of xerogels with different
chemical structure are discussed on the base of investigations of spectral-luminescent, acid-base,
photochemical and nonlinear-optical properties in solutions and solid matrices.
The subjects of investigations were: tetraazaporphyns and their metallocomplexes,
aminoderivatives of tetraphenylporphynes with coordinated Lu, complexes of phthalocyanines
and bisphthalocyanines with lanthanides also. These compounds were studied in liquid and
frozen solutions of ethanol, chloroform, DMSO and solid nanoporous xerogels with different
chemical structure under laser excitation by differ wave length (308, 532 nm) and intensity (3300 MW/cm2).
It was established, that all studied solutions and solid samples with incorporated tetrapyrroles
decrease the transmission of power nanosecond pulses compared with linear transmission on the
same wave length. It was specified by absorption of triplet-excited molecules and their
photocations which formed at the expense of ion-neutral shift under excitation.
The efficiency of ionic forms formation at the ground and electron-excited states and
phototransformations quantum yields of researched compounds were determined. The
mechanism of photocations participations at the tetrapyrrol compounds phototransformations is
discussed.
It is shown that proton’s phototransfer from solvent and hydroxyl groups on the surface of
pinholes of silica matrix (TEOS) to the protonoacceptor centers of tetrapyrroles is intensified
compared with liquid solutions.
The charachteristics of long-lived emission (ms) of some tetrapyrroles having a heavy atoms at
the structure, depending on solvent temperature and dissolved oxygen occurrence were
investigated. The capability of applications of investigated compounds as limiters of power
pulse laser emission, phosphorescent thin layers, optical sensors for determination of oxygen
occurrence and small quantities of acids is discussed.
Researches are supported by RFBR (grant 08-02-90003-Bel_a)
1. Evans R., Douglas P., Winscom Ch. // Coord. Chem. Rev. 2006. V. 250. P. 2093.
137
THE INVESTIGATION OF THE NO PHOTOADSORPTION
IN CO PRESENCE ON TiO2 HOMBIFINE N BY MEANS OF
KINETIC MASS-SPECTROMETRY AND THERMO-PROGRAMMED
DESORPTION SPECTROSCOPY
D.V. Laptenkov, R.V. Mikhaylov
St.Petersburg State University, Russia
ruslan@photonics.phys.spbu.ru
Titanium dioxide is widely used as photocatalyst in environmental catalysis, because it is highly
active in degrading many organic and inorganic pollutants, is resistant to photocorrosion and, at the
same time, is biologically and chemically inert and is of low cost. Earlier we had shown that the
photoreaction CO+NO+hν → N2 + CO2 (1) on TiO2 under irradiation in visible range takes place [1]
due to the light absorption by surface and/or bulk structure defects (oxygen vacancies, Ti3+ ions)[2].
The course of the reaction (1) was divided into two stages [1]. The first stage is characterized by a
decrease in NO concentration to nearly zero, appearance of N2O and formation of N2 (~5-8 % of NO)
after the light was switched on. The second stage is characterized by a decrease in CO and N2O
pressures in the gas phase and by an increase in N2 pressure up to approximately one half of the
initial NO pressure. CO2 was found to remain on the surface. The mechanism of reaction was
proposed [1].
The aim of the present work was to investigate the kinetic features and adsorbed phase composition
forming during of the first stage (NO photoadsorption) of reaction (1) on TiO2 Hombifine N at
various initial CO : NO ratios by means of kinetic mass-spectrometry and thermo-programmed
desorption spectroscopy (TPD).
The powder TiO2 Hombifine N (S = 320 m2/g) was chosen as a photocatalyst. The setup for massspectrometric measurements in the course of kinetic runs under static conditions and TPD
measurements was described previously [1]. A quartz reactor (16x35x3,5 mm3) filled with powder
TiO2 was used. The reactor was supplied with furnace allowing a linear heating and high-temperature
treatment of sample. A monopole mass spectrometer APDM-1 allowed one to scan up to 50 selected
mass peaks within the range 12–100 a.m.u. The experimental results were obtained at pressures of
gas mixtures 0.01 – 0.5 Torr and were corrected for gas sampling for analysis. High-purity (99.9%)
O2, NO, and 13CO (75% of 13C) were used. The samples were exposed to visible radiation (λ >400
nm) of a high-pressure mercury lamp (DRT-120) supplied with a water filter and a set of standard
glass color filters (LOMO, Russia). Photon fluxes were measured with a calibrated photocell F-17.
The heating rate in all TPD measurements was 15 K/min.
TiO2 samples were preliminarily heated at 870 K for 3 h in oxygen at a pressure of 0.5 Torr. Then,
partially reduced samples were obtained by heating the pretreated material under UHV conditions at
870 K.
It is found that reaction (1) takes place under visible light irradiation (λ >400 nm) on TiO2
Hombifine N. The first stage is characterized just by a decrease in NO concentration to nearly zero
after the light was switched on. The kinetic of NO photoadsorption depends on the CO amounts in
reactor indicating the transitional photoinduced processes of electron-type sites formation occurring
on the TiO2 surface in CO presence. The analysis of adsorbed phase composition after reaction first
stage by means of TPD reveals the desorption of CO (weakly bonded), N2O, NO and CO2. Basing on
TPD results the dependences of NO:N2O:CO2 ratios on initial NO and CO amounts were obtained.
This work was supported by RFBR under grant 09-03-00795-a.
1. A.A. Lisachenko, R.V. Mikhailov, L.L. Basov, B.N. Shelimov, M. Che, J. Phys. Chem. C, 2007,
v. 111. p. 14440.
2. Lisachenko, A.A.; Kuznetsov, V.N.; Zakharov, M.N.; Mikhailov, R.V., Kinet. Catal. 2004, 45,
189.
138
DIFFUSE REFLECTANCE SPECTROSCOPY FOR INVESTIGATION
OF GAS-SURFACE INTERACTIONS ON WIDE-BANDGAP OXIDES
A.A. Lisachenko
St.Petersburg State University, Russia
lisachen@photonics.phys.spbu.ru
A.N. Terenin was the first who had pioneered in 1930th the program of experimental
investigations of gas-surface interactions using the diffuse reflectance spectroscopy (DRS) in
UV-Vis-IR regions. This work was started under Terenin’s supervision and is followed in his
laboratory in the Physical Institute of Leningrad (St.Petersburg) State University up to now.
Some results of this work are discussed in the present report.
The dispersed powders of samples were investigated. In many works of Terenin's disciples the
vibrational spectra in the IR region are analyzed. These spectra are often well resolved and they
are characteristic for the adsorbed species structure. Another case is the electron excitation
spectra that occupy the UV-Vis region. The numerous absorption bands are broad and weakly
resolved. Two types of problems are studied using DRS:
1) The "Albedo" definition. For this for non-transparent samples the total reflected radiation
integrated over a hemisphere is measured. The absolute reflectance values are usually obtained
compared to an absolute reflectance of a standard. The remitted fraction of the incident radiation
flux, being always less than 1, is called "Albedo".
2) Another direction founded by A.N. Terenin consisted in the use of DRS for the investigations
of gas-surface interactions. The photometric procedure is based on the different reflectance
spectra before and after interaction. Since very complex processes are involved in the scattering
transmission and remission, so in practice DRS is used rather for qualitative investigations than
for quantitative ones. The two processes form a total remitted light flux. In the first one the
reflected light Rdiff originates in the interior of a powder as a result of multiple back light
scattering. For a non-transparent sample R∞diff is a function of the ratio K/S and not of the
individual values of absorption "K" and scattering "S". Both are non-linearly and in different
manner depending on wavelength and a particles size. In this case the increase of "K" entails the
decrease of R∞diff in accordance with the Kubelka-Munk theory.
Another term Rreg of remitted flux is formed by a regular reflection from the surface according to
the Fresnel-Beer law and is determined by the values or refractive "n" and absorption "K"
indexes. This term increases if "K" increases. Thus the two processes work against one another
and determine in common the spectral composition of the remitted radiation.
If the measuring irradiation causes a fluorescence in an absorption band of the sample, all the
fluorescence radiation is included in the measured remitted radiation. In such instances another
monochromator must be used for the remitted radiation.
The indicated problems are illustrated by real experimental spectra of gas-wide-bandgap oxides
interaction.
This work was supported by RFBR under grant 09-03-00795-a.
139
PHOTOINDUCED OXYGEN ISOTOPE EQUILIBRATION
ON TiO2-X SURFACE UNDER VISIBLE LIGHT IRRADIATION
A.A. Lisachenko, R.V. Mikhaylov, V.V. Titov
St.Petersburg State University, Russia
lisachen@photonics.phys.spbu.ru
Earlier we have shown that the photocatalytical reaction CO + NO + hν → N2 + CO2 on TiO2-x
under irradiation in visible range takes place [1] due to the light absorption by oxygen vacancies
and Ti3+ ions absorbing at 2.8, 2.5 and 2.0 eV [2]. The mechanism of reaction was suggested.
In order to test the stability of surface defects in the reduced sample under irradiation in oxygen
atmosphere and to test the photocatalytical activity in the absence of the reducing agent CO, the
photoinduced oxygen isotope equilibration (POIE) 16O2 + 18O2 → 216O18O on TiO2-x was
investigated.
Experimental. The Degussa P-25 TiO2 powder (S =50 m2/g) was preliminarily purified by
heating in oxygen flow at the pressure of 0.5 Torr for 10 hours at 870 K and then reduced by
heating in vacuum at 870 K for 10 min.
The experimental procedures of mass-spectrometric measurements in static and dynamic
conditions were described earlier [2]. POIE measurements were performed in flow-through
regime under oxygen pressures 10-5 – 10-3 Torr. High purity 18O2 and 16O2 were used to prepare
nonequilibrium oxygen mixture. The samples were exposed to visible radiation (λ=436 nm) of a
high-pressure mercury lamp (DRT-120) supplied with a water filter and a set of standard glass
color filters SS-15 and JS-11 (LOMO). Photon fluxes were measured with a calibrated photocell
F-17.
Processing. In case of flow-through regime the equation describing the OIE reads:
dY/dt = - KY+(Y0-Y)/τ,
where Y – is a parameter describing the non-equilibrium of output mixture (Y = 2α(1-α)-[C34],
where α = [C34]+2[C36]), Y0 – is a parameter Y of input mixture, K – OIE rate constant, τ – is the
characteristic pump time (τ = 5 s). The key parameter of OIE is the absolute rate of reaction:
R = KN = KLτ,
where N – is the current number of oxygen molecules in the reactor volume, and L – is the
oxygen input flow.
Results and discussions. It was found that after switching-on irradiation on the POIE rate R
increases monotonously up to its stationary value R0. After switching off the light the reaction
continues ("memory" effect), and R slowly drops down to zero. The increasing and dropping
branches could be approximated with exponential functions: Rincr = R0(1-exp(-t/τincr)) and Rdecr =
R1-0exp(-t/τ1decr)+ R2-0exp(-t/τ2decr), respectively. No changes of total pressure occurred during
POIE indicating the invariability of the adsorption-desorption equilibrium.
The values of R0 and τ1decr depend on oxygen pressure P whereas τ2decr and increase time τincr do
not change significantly with pressure. The stationary exchange rate R0 and both decrease times
τ1decr and τ2decr diminish with temperature in range 290 – 470 K at a constant pressure. However,
τincr is not affected by temperature in the range 290 – 370 K. The value of turnover number
(TON) exceeds 50, i.e. the reaction is really the photocatalytical one.
Both the model of the dissociative-associative reaction route via mobile ionic species 16O- and
18 O and the alternative associative-dissociative model assuming the formation of four-atomic
oxygen complex O4- are acceptable.
This work was supported by RFBR under grant 09-03-00795-a.
1. A.A. Lisachenko, R.V. Mikhailov, L.L. Basov, B.N. Shelimov, M. Che, J. Phys. Chem. C, 2007, v.
111. p. 14440.
2. Lisachenko, A.A.; Kuznetsov, V.N.; Zakharov, M.N.; Mikhailov, R.V., Kinet. Catal. 2004, 45, 189.
140
EFFECTS OF DONOR STRUCTURE ON TRIPLET ENERGY-TRANSFER
FROM AMINES TO ALKENE IN SOLUTION
G.V. Loukova, A.V. Lukov, V.A. Smirnov
Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
gloukova@mail.ru
Effects of the energy-donor and acceptor structure and their intermolecular interactions on
effectiveness of resonant energy transfer account almost silent observations. Notably,
unsaturated hydrocarbons are the substrates for catalytic systems of many organic syntheses,
therefore, study of intermolecular interaction/ electronic communication in multi-component
highly-organized systems in liquid and solid phase are of special interest. Olefins possess highlying singlet states and energy of S1–T1 gap and therefore are useful as triplet energy acceptors.
However, having unsaturated C=C bond, olefins can form complexes with metal complexes, as
well as organic compounds. Respectively, it is of importance to study energy transfer at different
conditions (varying solvents, electronic and structural features of the energy donor, etc.)
Phosphorescence quenching of structurally-related aromatic amines with hexane-1 was studied
in glassy solutions (largely, in ethanol) at 77 K. Such experiments in glassy/ solid media rule out
dynamic component of ET that is characteristic for liquid phase. Effectiveness of energy transfer
from emissive Т1-states of the aromatic amine series to Т1-state of olefin in solution at 77 K is
well described by the Perrin equation viz. Φo/Φ = exp(N·V·[A]) for electron-exchange
mechanism of interaction. Characteristic quantity for electron-exchange resonant energy-transfer
effectiveness in this case is the critical radius Ro. For small concentrations of amines (С ≤ 10–4
моль/л), values of Ro were estimated from the Perrin equation, including 10.8 Å (donor aniline),
7.6 Å (diphenylamine), 7.2 Å (3-methyldiphenylamine), 6.9 Å (carbazole), 6.1 Å (Nethylcarbazole), 6.4 Å (4,4'-dimethyldiphenylamine) and so on. Our data agree with assumption
that Rо depends on structural features of the energy donor and reflects degree of orbital and
quasi-chemical interactions in solution. We suppose that the critical radius of sphere for electronexchange energy-transfer to olefin decreases with enhance in steric hindrance of phosphorescing
donor molecules upon other close conditions (closeness of Т1-states of amines in energy and
spectral features, and, therefore, integrals of absorption and emission spectra overlap, etc.) It
should be noted that earlier, in the study of emission quenching of rare-earth metal salts with
organic compounds in acetone solutions, it was suggested that steric hindrance from amines are
responsible for the reduction in energy-transfer rate constants in the case of triplet energy
acceptor triphenylamine and N-methyldiphenylamine.
Acknowledgement. The authors gratefully acknowledge Professor A.E. Shilov for stimulating
discussion and Russian Foundation for Basic Research (grant N 09-03-00379) and Russian
Academy of Sciences for financial support.
141
ENERGY TRANSFER IN MOLECULES AND MOLECULAR SYSTEMS
G.V. Mayer, V.Ya. Artyukhov
Tomsk State University, Russia
artvic@phys.tsu.ru
Influence of intermolecular interaction on spectral-luminescent characteristics of molecules and
molecular systems always was an actual problem of molecular photophysics. One of the most
interesting displays of this interaction is connected to nonradiative photoprocesses – energy
transfer of electronic excitation between two chromophores. For interpretation of experimental
results of research on energy transfer the phenomenological model and quantum-mechanical
theory Ferster-Dexter is used. This theory allows to establish dependence efficiency of energy
transfer from spectral -luminescent properties of molecules of a donor and an acceptor.
In spite of the fact that this theory is not created for the description of energy transfer of
electronic excitation between chemically connected molecules of the donor and an acceptor in
bichromophore, it is widely applied to such systems. Typical bichromophoric molecules consist
from donor and acceptor fragments which are connected in a uniform molecule by the bridge
which is not transmitting electronic conjugation.
In any polyatomic molecule after absorption of light quantum there are certain photophysical
processes of transformation of excitation energy. Also it was quite natural to assume, that
process of energy transfer of electronic excitation in bichromophoric molecules is realized by
means of one of them. The main idea of our approach to an investigated problem consists in
performance of quantum-chemical calculations of bichromophores as uniform molecular system
without division into molecules of the donor and an acceptor (model of "supermolecule") with
the subsequent estimation and the analysis of the photophysical processes occuring in such
molecules. Starting the end of 80th years we carried out theoretical researches of the
phenomenon of electronic excitation energy transfer in bichromophoric organic compounds and
molecular systems. During researches it has been developed quantum-chemical model of
studying of the orbital nature and spatial localization of electronic states and features of course of
photoprocesses in such systems.
In the present research bichromophores made on a basis of anthracene and naphthalene have
been chosen. These molecules are well investigated experimentally and theoretically, that
provides an opportunity of comparison of results with experimental data, and, hence, correct
reproduction in quantum-chemical calculations the properties, both molecules, and compounds
on their basis. The bichromophoric compounds with bridges of various length, a spatial structure
and rigidity were investigated. For each molecule are calculated a little various conformations.
Also bomolecular systems with the same spatial arrangement of molecules, as in
bichromophores, are calculated.
For all molecules and systems the rate constants of photophysical processes have been estimated.
The results of calculations show, that in the investigated cases energy transfer of electronic
excitation is carried out on the mechanism of internal conversion. The value of a rate constant of
energy transfer depends on mutual orientation of a donor and an acceptor, distance between
them.
Influence of relative orientation of chromophores cannot be expressed simple analytical
expression, as in the Ferster theory. On small distance between chromophores mutual orientation
influences insignificantly on efficiency of energy transfer. Besides, influence of relative
orientation of chromophores can mask presence of several channels of energy transfer.
As a whole, results of the quantum-chemical approach to research of process of energy transfer
are more productive and allow to explain features of this process more in details.
142
PROBE PHOSPHORESCENCE AND TRIPLET-TRIPLET
ENERGY TRANSFER IN THE STUDY
OF CONFORMATIONAL CHANGES IN THE PROTEINS
A.G. Melnikov1, V.I. Kochubey1, A.B. Pravdin1,
E.V. Naumova2, O.A. Dyachuk2, G.V. Melnikov2
1 - Saratov State University, Russia
2 - Saratov State Technical University, Russia
melnikov_gv@sstu.ru
In this work we investigate processes of radiation and radiationless deactivation of electronic
excitation energy of the polar and nonpolar luminescent probes bound to immunoglobulin,
human serum albumin (HSA) and human blood plasma albumin. We chose xanthene dyes such
as eosin, erythrosine and others as polar luminescent probes and polycyclic aromatic
hydrocarbons (PAH) such as anthracene, pyrene and others as nonpolar luminescent probes.
Investigation of the interaction of chosen reagents with proteins is urgent by several reasons.
Firstly, most PAHs are cancerogen, and processes of their interactions with proteins are
interesting for medicine. Secondly, this is known that xanthene dyes are used in photodynamical
therapy. Thirdly, investigation of the mono- and bimolecular deactivation processes of electronic
excitation energy are of scientific interest for development of the photonics methods in native
systems research.
Obtained absorption and fluorescence spectra of the probes made it possible to establish that
polar dyes molecules and nonpolar PAHs get bound to the proteins. Absorption coefficients of
several xanthene dyes and PAHs bound to proteins were determined. Delayed fluorescence (DF)
and room temperature phosphorescence (RTP) of the probes bound to immunoglobulin, human
serum albumin and blood plasma albumin were observed in oxygenless solutions. Significant
increase of the intensity DF and RTP of the dyes and their lifetime on going from aqueous
solutions to proteins indicates that probes bound to proteins are immobilized. We suggest the
method for determination of the constants of probes binding to HSA globules, based on probes
phosphorescence quenching by iodine ions in aqueous HSA solutions. The use of low
concentrations of quencher (sodium idodide) for observing of the phosphorescence of the
xanthene dyes is the advantage of method, because at these concentrations properties of the HSA
globules do not change. On the base of obtained results we concluded that efficiency of
quenching of the xanthene dyes molecules bound to HSA globules by water-soluble compounds,
containing heavy atoms, are determined by interactions of the dyes molecules with proteins.
Triplet-triplet energy transfer (TET) of electronic excitation energy between xanthene dyes and
anthracene both bound to immunoglobulin, human serum albumin and blood plasma albumin
was observed. So far as anthracenу are insoluble in water, TET is possible only in the protein
globule. Rate constants of the TET energy transfer were determined subject to localization of
donor and acceptor molecules in the protein globules.
We found out that the rate constant of the energy transfer is sensitive to conformational changes
of the protein globule under the action of surfactants. It is shown that triplet-triplet energy
transfer method is applicable for registration of the intramolecular structural changes in protein
globule.
143
COMBINED KINETIC, UV-VIS, FTIR AND TPD STUDY OF THE
PHOTOCATALYTIC NO REDUCTION BY CO ON TiO2
R.V. Mikhaylov1, A.A. Lisachenko1, B.N. Shelimov2,
G. Martra3, S. Coluccia3, M. Che4
1 - St.Petersburg State University, Russia
2 - N.D. Zelinsky Institute of Organic Chemistry RAS, Moscow, Russia
3 - Turin University, Turin, Italy
4 - Université P. et M. Curie, Paris, France
lisachen@photonics.phys.spbu.ru
Photocatalytic removal of organic and inorganic pollutants from indoor air is being intensively
investigated. In most cases, titanium dioxide is used as a photocatalyst owing to its high activity,
versatility, non-toxicity and low cost. Here we report on environmentally important
photoassisted selective reduction of NO by CO on self-sensitized Degussa P-25 TiO2 at room
temperature: NO + CO hν ½ N2 + CO2 [1]. It is found that the photocatalytic reduction of NO
can occur on TiO2 catalysts both upon UV (λ< 380 nm) and visible light (λ > 380 nm)
irradiation, in the latter case owing to the presence of electron-donor centers (Ti3+, F and F+
centers) in nonstoichiometric TiO2-x capable of absorbing visible light [2].The selectivity of the
photoreaction to N2 production attains 90-95%, N2O is being a minor product. Massspectrometric analysis of the gas phase shows that the CO2 formed by the reaction does not
desorb at 300 K suggesting formation of some carbonate or carboxylate stable surface structures
which could potentially be detected by IR spectroscopy. However, the CO2 produced could be
quantitatively desorbed after completion of the photoreaction by heating TiO2 to ~500 K.
A multistage reaction mechanism is proposed based on combination of mass-spectroscopic
kinetic analysis of gaseous reaction products with the studies of active centers in TiO2 by UV
photoelectron and UV-Vis diffuse reflectance spectroscopy. The reaction scheme involves some
N-containing surface intermediates (e.g., NO–, NO2– and N2O) which could be the objects of an
IR examination along with the above-mentioned C-containing species.
A deeper insight into the mechanism of NO photoreduction with CO has been gained by
studying successive reaction stages occurring in the adsorbed phase upon exposure of Degussa
P-25 TiO2 photocatalyst to NO, CO and NO–CO mixtures in the dark and under subsequent light
irradiation by means of FTIR and TPD spectroscopy. Only reversible weak adsorption of NO on
surface Ti4+ ions is found to occur in the dark. UV-Vis irradiation greatly enhances the NO
adsorption on Ti4+ and yields N2O, NO–, NO2– and NO3– surface species. After irradiation of
TiO2 in a CO atmosphere, IR bands of surface CO2– and CO3– species appear in addition to a
continuous IR absorption tail towards lower wavenumbers due to free carries in the reduced
semiconductor. When TiO2 is exposed to a equimolar NO–CO mixture, N2O and CO2– are
formed without irradiation supposedly by reaction 2 NO + 2 CO + O2– → 2 CO2– + N2O.
Subsequent light irradiation is accompanied by the accumulation of NO– and Ti4+…NO
complexes. No TiO2 reduction occurs in this case. FTIR spectra show that NO– produced by the
photo-induced adsorption of NO can be eliminated by reaction: NO– + CO hν CO2– + ½ N2. It
is believed this reaction is a key step in the nitrogen production by the photocatalytic process.
The data obtained enable us to refine the earlier proposed reaction mechanism and to directly
prove some of its key steps.
1. A.A. Lisachenko, R.V. Mikhailov, L.L. Basov, B.N. Shelimov, M. Che, J. Phys. Chem. C, 2007, v.
111. p. 14440.
2. A.A. Lisachenko, R.V. Mikhaylov, L.L. Basov, B.N. Shelimov, M. Che, High Energy Chemistry,
2008, v. 42, p. 80.
This work was supported by RFBR under grant 09-03-00795-a
144
MATHEMATICAL SIMULATION OF STRATEGY FOR THE CONTROL
OF EXCITED- STATE INTRAMOLECULAR REVERSIBLE PROTON
TRANSFER IN THE MULTIPARAMETRIC FLUORESCENCE PROBES
V.A. Morozov
N.D. Zelinsky Institute of Organic Chemistry RAS, Moscow, Russia
morozov@mail.ioc.ac.ru
Mathematical simulation, reversible proton transfer, multiparametric fluorescence probes.
The study of the fluorescence molecular probes to definite the different types of intermolecular
interaction simultaneously has been a large interest in the last year. For example, 3hydroxyflavone and 3-hydroxychromone molecules were founded to fulfill the criteria of such
multiparametric fluorescence probes [1]. A detailed knowledge of intramolecular dynamics of
such molecules at transformation of light with two bands in fluorescence emission is necessary
to successfully use these molecules as sensors. The knowledge may be obtained as a result of a
comparison between the mathematical simulation of intramolecular dynamics at such
fluorescence and corresponding experimental data. Dual fluorescence is connected with fourlevel molecular electronic systems which may be (following through [2]) as a result of the
excited-state intramolecular proton irreversible or reversible (“coherent tunneling”) transfer at
the enol-keto-photoisomerization. Mathematical simulation of the irreversible intramolecular
proton transfer at the enol-keto-photoisomerization was carried in [3]. In the present report, the
results of the similar modeling the excited-state intramolecular proton reversible transfer at
photoisomerization of four-level molecule with exposed two light pulses (“pumping” pulse and
the “probe” or “dump” pulse) are given. Simulation was conducted basing a numerical solution
of a system of equations for the density matrix of model molecule at the different values of two
classical described irradiation pulses. A set of values of parameters of light pulses were
determined at which after the enol-keto-photoisomerization of model molecule induced by
pumping pulse, the probe pulse lead to forced transition of the molecule from the tautomer
excited electronic state to the ground electronic state of this form with the increment of
photoisomerization effectiveness. Corresponding temporal changes of the molecular states
population is obtained and shown on the pictures. The obtained results can serve as reference
points at interpretation of the spectral-temporal experimental photoisomerization data for the
molecules with a proton bond under irradiation of the molecule by two light pulses, to establish
the mechanism of the excited-state proton phototransfer and to control the process by second
light pulse.
The work was partly supported by Program №1 of the Department of Chemistry and Materials
Science, Russian Academy of Sciences.
1. A.P. Demchenko, A.S. Klymchenko, V.G. Pivovarenko et al. “ Multiparametric ColorChanging Fluorescence Probes”. Journal of Fluorescence. Vol. 13. No. 4. 2003.
2. M. Kasha. “Proton-transfer Spectroscopy”. J. Chem. Soc. Faraday Trans. Vol. 282. P. 2379.
1986.
3. V.A. Morozov. “Numerical Simulation of Intramolecular Dynamics during Dual Fluorescence”. Optics and Spectroscopy. Vol. 105. No. 2. P. 176.
145
PREPARATION OF MAGNESIUM PHTHALOCYANINE
NANOCRYSTALS
S.S. Nadolinskaya1, A.M. Meshkov2, V.G. Maslov2, V.I. Korotkov1
1 - St.Petersburg State University, Russia
2 - St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
korotkov@paloma.spbu.ru
Phthalocyanines characterize very high thermal, photo, chemical stability and photoelectrical
sensitivity. Due to this their properties they are used as photosensitive devices in modern laser
printers, optical disks and as photochemical redox agents in solar conversion.
Special interest arises for preparation and investigation phthalocyanine nanocrystals because
their spectral, luminescence and photophysics properties change very significantly comparison
with molecular properties. Conversion of some phthalocyanines from molecular to a crystalline
state drastically changes the photophysical and photochemical properties. Therefore nanocrystals
provided to be quite perspective objects for investigation.
We choose Mg phthalocyanine as object for investigation on the basis of its similarity and
relationship to chlorophyll. Now there are some articles describe method of preparation microand nanosized crystals of magnesium phthalocyanine. Phthalocyanine crystals have been
preparated by addition water into solution of Mg phthalocyanine in acetone. Water acts as
“salting out” solvent. Size of crystal limits by volume of adding water, temperature and time of
crystallization. Final fixing of crystal dimension acts by introduction binding polymer into
colloidal solution. Some times magnesium phthalocyanine did not dissolved in acetone — during
long storage crystals come to stable crystal modification due to polymorphic conversion.
Acetone does not dissolve these crystals.
Herein we developed new method for fabrication nanocrystals of magnesium phthalocyanine: as
solvent we used sulfuric acid. This acid very effective dissolves all crystal modification of
magnesium phthalocyanine. Water was also “salting out” solvent. To avoid presence of acid and
dissolving increased crystals acid has been “washout” from solution. Also this procedure was
used for fixation size of crystal. Process of pigment crystallization was controlled by arising new
bands of electronic absorption intrinsic Mg phthalocyanine.
Absorption spectra of crystals, grown by our method, vary from spectra known individual crystal
forms. The complex structure of the spectra of our samples is attributed to the simultaneous
presence of some crystal phases and the molecular phase of Mg phthalocyanine in the samples.
According to the literature data absorption band near 675 nm belongs a-form of nanocrystal of
pigment, broad spectrum in region 550–850 nm with the main maximum at 700 nm is
characteristic forb-form, intensive absorption band at 825 nm corresponds to x-phase.
Registered spectra clearly demonstrated appearance of broad intensive band in zone 500–850 nm
with clearly distinguished maxima at 630 and 700 nm. Maximum at 630 nm apparently
correspond absorption band of the molecular phase of Mg phthalocyanine. Maximum at 700 nm
– absorption band of the b-form. Also probably there is presence of a-phase. Absence of
absorption band at 825 nm implies that x-phase of Mg phthalocyanine in such conditions does
not generates.
Therefore one can conclude that proposed method of preparing of Mg phthalocyanine
nanocrystals produces mainly b-form nanocrystals.
146
PHOTOCHEMICAL TRANSFORMATIONS OF CHALCONE PODANDS
IN THE CRYSTALS AND SOLUTIONS
I.G. Ovchinnikova1, O.V. Fedorova1, A.V. Druzhinin2,
G.L. Rusinov1, V.N. Charushin1
1 - I.Ya. Postovsky Institute of Organic Synthesis RAS, Ekaterinburg, Russia
2 - Institute of Metal Physics RAS, Ekaterinburg, Russia
iov@ios.uran.ru
In connection with search of new principles of information recording and working out of its
carriers turn to the technologies related to engineering of high-organized controlled molecular
structures, being an object of research of supramolecular chemistry, is obvious. One of the most
promising macromolecular compounds containing photo-operated groups and, hence, capable to
transform light energy into chemical bond energy can be chalcone podands. In this regard the
synthesis of podands with 2-oxybenzylideneacetophenone fragment 1a-c is carried out and their
photochemical transformations into a solid-state and solutions are investigated.
O
O
n
O
O
*
O
n
O
∆λ 328 - 496 nm
O
n
O
t c
O
t
t
O
O
O
C(O)Ph
C(O)Ph
O
n
α
hν
O
β
n
O
O
Ph(O)C
m
solid
Ph
O
O Ph
C(O)Ph
1a-c
2a,b
n = 1, m = 1 (a);
n = 2, m ~ 100 (b)
Ph
n
O
O Ph
O
O
Ph
Ph
O
O
n
O
O
r c
Ph
3a,b
Ph
5a-c
hν
KSCN
CH3CN
(DMF)
O
r t
+
*
O
O
O
Ph
O
O Ph
O
n = 0 (a), 1 (b), 2 (c)
O
n
t t
c c
n
O
O
O
. .
r t
Ph
∆λ 258 - 400 nm
O
O
Ph
r
O
n
O
O
O Ph
O
c
Ph
Ph
4a-c
6b,c
Ph
Distinctions in the parameters of chalcone podand preorganization to intermolecular
photoinduced [2+2]-cycloaddition in crystals are revealed. It was found that the chalcone-podand
1b (n=1) forms stereoregular cyclobutane containing polymer chains 2b throughout a single
crystal. In a case of chalcone podand 1a (n=0) photocycloaddition becomes impossible in the
single crystals, however mechanical destruction of crystals leads to the formation of superficial
with π-stacking dimers layers in which photodimerization proceeds by reducing topotactic
control from a molecular lattice with formation of dipodand 2a.
On the contrary, in solutions chalcone podands in the presence of templates (alkali metal ions)
enter into intramolecular reaction of photocycloaddition with formation of corresponding
cyclobutane containing dibenzo-crown-ethers 3-6. With application of such methods as X-ray,
UV, 1H and 13C NMR spectroscopy it has been shown that the reaction of intramolecular
stereoselective dimerization takes place (with the formation mainly of structures β- and γtruxinic type), the speed of photoinduced [2+2]-cycloaddition depends on the size of oxyethylene
spacer and stereoorientation of chalcone fragments in the podands. Also, it has been found that
the selectivity of photocycloaddition can be regulated by change of template concentration and
variation of the range of light irradiation.
Work is executed with financial support of the Russian Foundation for Basic Research (grants №
07-03-96111, 07-03-96113); the Presidium of the Russian Academy of Science (the project
«Design of new supramolecular structures containing heterocyclic fragments»).
147
TWO-PHOTON PHOTOPROCESSES IN MOLECULAR SYSTEMS
V.G. Plotnikov1, V.A. Smirnov2, M.V. Alfimov1
1 - Photochemistry Center RAS, Moscow, Russia
2 - Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
vas@icp.ac.ru
Two-photon processes occurring in polyatomic molecules in condensed phase are reviewed.
Mechanism and kinetics of the light second photon consumption and regularities of fundamental
two-photon processes: ionization, electronic excitation energy transfer, dissociation with
hydrogen atom and molecular products elimination are discussed. Experimental state of art of the
method is demonstrated. One of the main requirements to the molecules of effective polymer
photostabilizers is highlighted to be the absence of two-photon processes which is possible at
effective radiationless conversion, initiated by reversible adiabatic chemical reactions. Based oh
this idea, properties of main types of polymer stabilizers is interpreted.
148
FTIR STUDY OF METHANE INTERACTION
WITH OXIDE ADSORBENTS
M.S. Poretskiy, A.A. Tsyganenko
V.A.Fock Institute of Physics, St.Petersburg State University, Russia
tsyg@photonics.phys.spbu.ru
Low temperature adsorption of methane and deuterated methane (CHD3) has been studied by IR
spectroscopy on zeolites: CaY, SrY, ZnY, NaY, RbY, KY, CsX, RbX, NaX, mesoporous MCM41 silica, and oxides CaO, ZnO, ZrO2, TiO2 in order to find out spectral manifestations of
adsorption, nature of surface sites and the structure of adsorbed complexes. Spectra were
compared with those of CO adsorbed on the same adsorbents, and besides the shifts of the
absorption bands, extinction coefficients ε were measured, in particular, for ∆ν1 vibration.
The frequency shifts of methane ν1 band increase regularly with the electron accepting ability of
cationic sites characterized by the value of blue frequency shift of adsorbed CO, which increases
in the sequence: MCM-41>RbY>HY>NaY>SrY>CaY>ZnY. Comparison of these data shows
that the bands below 2900 cm-1 cannot be attributed to ν3 vibration, as proposed earlier [2] for
the most intense bands at 2850-2895 cm-1 in the spectra of CH4 on mordenites, but is rather due
to the ν1 mode of methane adsorbed on cationic sites. This is in accordance with our spectra of
adsorbed CHD3, which reveal no bands seriously shifted downwards.
The strongest sites of CO adsorption on X-zeolites or CaO are basic oxygen ions. One could,
thus, anticipate that methane adsorbed on CsX should also interact with electron donor oxygen
sites. The spectra of CH4 adsorbed on CsX, besides the band near 2900 cm-1, assignable to
interaction with residual Na+ cations, contain a band at 2876 cm-1, which can be attributed
neither to complexes with Na+, nor with Cs+ cations, and belong, apparently to methane
molecule bound by the H-bond-like interaction in CH4…O complexes with oxygen atoms. CO
adsorption on CaO, besides the comparatively weak interaction with the cations, leads to the
formation of carbonite CO22- species as a result of adsorption on electron donor surface oxygen
ions [1]. The band of ν1 mode of CH4 on CaO at 2885 cm-1 does not fit the above correlation for
the cationic sites, and should also be assigned to methane adsorbed on surface oxygen ions. This
conclusion is supported by the results of experiments with CO addition to CaO with preadsorbed
methane, which demonstrate a competitive adsorption of both the molecules on the same anionic
sites.
According to quantum-mechanical calculations, with cationic sites methane should form
complexes, where three CH bonds are directed towards the cation, and the fourth oriented
outwards [3]. For the complexes with anions one could expect, on the contrary, one CH bond
directed towards the anion, as in the case of fluoroform, which forms weak H-bonds with protonaccepting oxygen centers. However, in such a case methane should reveal a blue shift of CH
vibration [4], but neither CH4 nor CHD3 adsorbed on basic adsorbents, such as CaO manifest any
CH stretching frequency increase. To explain this contradiction, we can even adopt for the C-H
bond in methane very weak, but opposite polarity, like in the case of hydride-like B-H bond.
Then the geometry of complexes should be different, but the observed red frequency shifts
would be consistent with the data of calculations. The question of the geometry of surface
methane complexes still needs new experimental data.
The work was supported by RFBR, grants 06-03-32836a and 06-05-64646a.
References:
[1] Babaeva M.A., Bystrov D.S., Kovalgin A.Yu., Tsyganenko A.A. J. Catal., 123 (1990), 396.
[2] Khodakov A.Y., et al. J. Chem. Soc. Faraday Trans., 89 (1993) 1393.
[3] Knozinger H., Huber S., J. Chem. Soc. Faraday Trans., 94 (1998), No 15, 2047.
[4] K. Hermansson, J. Phys. Chem. A, 106 (2002) 4695.
149
LUMINESCENT INVESTIGATION OF ACRIDINE
HOMO-CONJUGATED COMPLEX
J.A. Rozhkova1, A.A. Gurinov2, S.B. Lesnichin1,
I.G. Shenderovich1, V.G. Maslov3, V.I. Korotkov1
1 - Physics Department, St.Petersburg State University, Russia
2 - Chemistry Department, St.Petersburg State University, Russia
3 - St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
korotkov@paloma.spbu.ru
Essential methods to studying of hydrogen bond are NMR and IR-spectroscopy. At last time one
begins to use optical UV-Vis spectroscopy. It is worth seeing luminescence to examine hydrogen
bond. This method characterizes considerable sensitivity in comparison with UV-Vis
spectroscopy, NMR and IR-spectroscopy.
Therefore it has been investigated luminescence spectra of acridine and protonated form of
acridine – acridinium with counter-ion BARF. Also we took attempt to detect luminescence
spectrum of homo-conjugated complex acridine + acridinium. Acridine was selected for studying
because of its absorption spectrum exposed the greater changes under protonation in comparison
of other nitrogen-containing aromatic compounds - pyridine, collidine, quinoline, quinaldine which we optically studied previously. Dichloromethane was used as aprotonic solvents.
Luminescence spectra and excitation luminescence spectra of solutions of acridine, its
protonated form – acridinium and mixture of acridine and acridinium at room temperature has
been studied. There are intensive maximums at 290 nm, 320 nm, 400 nm, 418 nm and 440 nm in
luminescence spectra of acridine under different wavelengths of excitation. Excitation
luminescence spectra were detected for all these maximums.
Luminescence spectra of acridinium solution exposed considerable rising of intensity and
significant long wave displacement in comparison of spectra of acridine – maximums locate at
460 nm, 480 nm and 525 nm. This effect can be explained by the change in the most important
fluorescence parameters. Introduction onto molecule of a strong electron-donor group usually
causes dramatic changes in all spectral-luminescent parameters. The oscillator strength of the
S0→S1 electronic transition usually increases and, as a rule, the fluorescence quantum yield also
increases. Probably protonation results in analogous effect.
Luminescence spectrum of mixture of acridine and acridinium consists of all above enumerate
maximums. Mathematical treatment of these spectra shows difference between luminescence
spectrum of mixture and superposition of acridine spectrum and acridinium spectrum. Addition
of acridine and acridinium spectra with different coefficients does not give spectrum of mixture.
We calculated remainder between spectrum of mixture and sum of acridine and acridinium
spectra. This difference spectrum, with two maximums at 440 nm and 470 nm, hypothetically
attributed to homo-conjugated complex acridine + acridinium.
150
PROTONATED NITROGEN-CONTAINING AROMATIC MOLECULES.
SPECTROSCOPIC INVESTIGATION
J.A. Rozhkova1, A.A. Gurinov2, S.B. Lesnichin1,
I.G. Shenderovich1, V.G. Maslov3, V.I. Korotkov1
1 - Physics Department, St.Petersburg State University, Russia
2 - Chemistry Department, St.Petersburg State University, Russia
3 - St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
korotkov@paloma.spbu.ru
Many works devoted to study of hydrogen bond by NMR and IR-spectroscopy. Optical UV-Vis
spectroscopy provides a supplementary interpretation of experimental data on hydrogen bond
and proton transfer phenomena, obtained using different methods. But in many cases the
limitation of UV-Vis is the absence of measurable differences between spectra of free and
protonated species.
Nitrogen-containing aromatic compounds: pyridine, collidine, quinoline, quinaldine. acridine
were experimentally studied by UV-Vis spectroscopy. Heterocyclic bases are convenient objects
for investigation because their proton-accepting abilities can be selectively varied by introducing
substitutes in meta- and para-positions. Besides that steric effects can be controlled using orthosubstitutions. The higher is the proton-accepting ability of a molecule the stronger a competition
of two equivalent molecules for the proton in their homo-conjugated complex is.
Dichloromethane and chloroform were used as solvents. To investigate the dependence of
counter-ion size on spectra of protonated species we used BrF4 and BARF.
Optical spectra of protonated species for both “small” BrF4 and “large” BARF ions
demonstrated appearance of absorption bands in the long-wave region of spectra and decrease of
the intensity of absorption band in the short-wave part. The long-wave border of the spectra
moves to 290 nm in the case of the pyridinium, to 292 nm in the case of the collidinium, and to
345 nm for quinaldinium. The largest shift of the long-wave limit has been revealed in the
acridinium absorption spectrum. The spectrum of acridinium differs from the acridine spectrum
by disappearance of a maximum at 380 nm and by appearance of new absorption bands in the
region 400 – 460 nm and in the short-wave region 270-290 nm. Also after protonation of the
acridine molecule one can see in the absorption spectrum a shift of a maximum at 357 nm
towards the short-wave part to 1nm.
It was shown by NMR that investigated molecules and its protonated species form in solutions
homo-conjugated complexes. These complexes are forming due to hydrogen bonding between N
atom of heterocyclic base and proton of its protonated species. To reveal such complexes in UVVis spectra we used titration method: solutions of a heterocyclic bases were added by small parts
to solutions of protonated species. The absorption spectra of homo-conjugated complexes were
calculated from the absorption spectra of mixtures.
Hydrogen bonds in such complexes are weak. Hence the dynamic equilibrium between isolated
species and their hydrogen bonded complexes in solution is temperature dependent. The relative
concentrations of homo-conjugated ions increase upon cooling. For example, for a mixture of
quinoline and quinolinium in chloroform the absorption in the region 290 – 330 nm increases
upon cooling from 200 to -650 C that indicate a disposition of homo-conjugated complex
absorption spectrum in this spectral region.
151
ETHYLENE PHOTOPOLYMERIZATION ON ZEOLITE NA–ETS-10:
IR SPECTROSCOPIC STUDY
A.V. Rudakova1, R.F. Lobo2, V.K. Ryabchuk1, K.M. Bulanin1
1 - V.A. Fock Institute of Physics, St.Petersburg State University, Russia
2 - Department of Chemical Engineering, University of Delaware, Newark, USA
brigg7@yandex.ru
The photocatalytic activity of ETS-10 titanium silicalite has been known to significantly differ
from the activity of a traditional Ti2O photocatalyst [1]. This material has attracted increased
attention because of particular features of its structure, which contains a three-dimensional
network of channels of large cross-section, formed by twelve-membered rings. Such a structure
has significant advantages for catalysis and photocatalysis because of better condi-tions for
diffusion of molecules in pores and because of the possibility for selecting molecules with the
desired shape and size.
In this work [2], we studied UV induced polymerization of ethylene on Na–ETS-10 titanium
silicalite by IR spectroscopy. The local structure of the adsorbent was studied with the help of
Raman spectroscopy. The data obtained from the IR spectra were analyzed using 2D correlation
spectroscopy initially proposed first by Noda [3-4].
It was found that reaction being under study proceeds at room temperature yielding
polyethylene. We suggest that holes O• generated by the UV radiation in –Ti–O–Ti– chains can
initiate the reaction of polymerization of ethylene by the following mechanism:
О–• +H2C = CH2 → О – СH2 – СH2 – CH2 – ... .
2D correlation spectra supported well conclusions obtained from the experimental data.
References
1. Southon P.D., Howe R.F. // Chem. of Mater. 2002. V. 14. № 10. P. 4209-4218.
2. Rudakova A.V., Lobo R.F., Bulanin K.M. // Optics and Spectroscopy. 2008. V. 105. № 5. P.
739-744.
3. Noda I. // Bull. Am. Phys. Soc. 1986. V. 31. P. 520.
4. Noda I., Ozaki Y. Two–dimentional Correlation Spectroscopy - Applications in Vibrational
and Optical Spectroscopy. John Wiley&Sons Ltd, 2004.
152
PHOTO-OZONOLYSIS OF CHLORINATED ETHENES AND
HYDROGEN CYANIDE ON WATER ICE FILMS
A.V. Rudakova, I.L. Marinov, A.A. Tsyganenko
V.A. Fock Institute of Physics, St.Petersburg State University, Russia
ilya.marinov@gmail.com
Photochemical transformations and photo-induced oxidizing processes on ice surfaces as well as
in the bulk of ice particles are of a great importance for atmospheric science, ecology and
astrophysics. In this work, photo-ozonolysis of chlorinated ethenes and hydrogen cyanide on/in
icy films has been investigated by means of FTIR spectroscopy at 77 – 200 K. The cell for
spectral studies of adsorbed molecules at variable temperatures (55-370 K), described elsewhere
[1], was equipped with a device for vapour sputtering from the heated capillaries and deposition
onto the inner BaF2 windows of the cell, cooled by liquid nitrogen. The systems under
investigation were irradiated by a 120-W high-pressure mercury lamp DRK-120 (MELZ). Ozone
was produced from O2 by electric discharge.
Ozonolysis of C2H3Cl, gem-, cis- and trans- dichlorethenes and C2Cl4 adsorbed on D2O ice film
has been studied. It was found that ozone co-adsorption with C2H3Cl at 77 K readily leads to
ozonolysis reaction, while for the three isomers of C2Cl2H2 it starts only at 120 – 150 K. For
C2Cl4 co-adsorbed with O3, ozonolysis reaction doesn’t occur even at 200 K, however, UVirradiation of this system leads to appearance of new bands already at 77 K. For the same
compound, such as gem- C2Cl2H2, the poducts of photo-ozonolysis and ozonolysis at higher
temperatures are not the same, testifying for different mechanisms of these reactions. Analysis of
these data infers that mechanism of ozonolysis can be described by Criegee scheme, and leads to
formaldehyde, formyl chloride, phosgene and CO2 as ultimate products. The latter two were also
found among the products of photo-ozonolysis.
Ozone adsorption on solid HCN film at 77 K in the dark doesn’t manifest any changes in the
spectra, while under UV irradiation new products appear. In order to identify the products
isotopic experiments with DCN and 18O3 were carried out, as well as photolysis of pure NO
adsorbed on water ice film and photo-ozonolysis of solid N2O film. Photolysis of HCN was not
detected at the conditions of experiment. Studies of HCN photo-ozonolysis dependence on the
wavelength of incident radiation has shown that the spectrum of acting light coinsides with the
Hartley band at 200-300 nm. Apparently, this is photodissociation of ozone which accounts for
photo-ozonolysis. According to the obtained spectral data, isocyanic acid (HNCO) is an
intermediate product of this reaction, while CO2 and NxOy seem to be the ultimate products.
Photo-ozonolysis of pure nitrous oxide film at 77 K results in formation of NO dimers. At the
same time photolysis of solid NO leads to N2O formation. The two photo-chemical processes,
thus, somehow counterbalance each other.
To investigate the influence of water addition on the reaction mechanism, photo-ozonolysis of
hydrogen cyanide in mixed HCN/H2O ices at 77 K has been studied. The surface properties of
HCN/H2O ices with different component ratio have been tested by low-temperature CO
adsorption [2]. It was found that water admixture promotes faster HNCO formation during the
photo-ozonolysis process. Apparently, water also induces the dissociative ionization of HNCO
and formation of the cyanate ion (OCN¯). Thus, increase in the reaction rate is due to photoinduced isocyanic /cyanic acid (HOCN) isomerization.
Acknowledgments. The work was supported by INTAS (grant 03-51-5698) and RFBR (grants
06-03-32836 and 06-05-64646).
1. Otero Areán С. et al. Eur. J. Inorg. Chem., 2001, No 7, 1739.
2. Rudakova A.V. et al. Langmuir, 25 (2009), 1482.
153
THE EFFICIENCY OF UV STIMULATED FORMATION
OF ACTIVE CENTERS AT THE SURFACE OF MICROAND NANO-DISPERSED ZrO2 PHOTOCATALYSTS
V.K. Ryabchuk1, A.V. Emeline1, G.V. Kataeva2,
G.N. Kuzmin1, N.V. Sheremetyeva1
1 – V.A. Fock Institute of Physics, St.Petersburg State University, Russia
2 – Faculty of Natural Sciences, Dimitrovgrad Subdivision of Ulianovsk State University, Russia
ryabchuk@photonics.phys.spbu.ru
One of the major problems to design an efficient photocatalytic system for practical application
is the development of highly active photocatalyst. The decreasing of the catalyst particle size
seems to be a proper approach. It confirms by some simple models (see for example [1]).
However as known for titania photocatalysts, the model expectations are not fulfilled quite often
in practice.
The efficiencies of UV induced surface active centers formation for micro- and nano dispersed
zirconia photocatalysts have been compared in present studies. Zirconia powders with SBET = 7
m2/g and SBET = 71 m2/g (particle size d ∼ 100 and 15 nm respectively) have been studied. Here
we present two sets of experimental results. The first one is the kinetics of active surface centers
(color centers of V and F type) formation under UV illumination in micro dispersed zirconia
powders in vacuo and in gases compared with corresponding kinetic data obtained for nano sized
powders. In addition, the spectral dependencies of quantum yields of hydrogen and oxygen
photoadsorption on zirconia samples are also confronted.
The results can be summarized as following: 1) The photo catalytically active centers of the
same type (so called color centers of F and V type) are induced by UV light at the surface and in
near surface area of both micro and nano sized zirconia; 2) The total efficiency of such centers
formation under illumination in vacuo is of 5-10 fold higher for micro sized powders comparing
with the efficiency of photocoloration in nano sized zirconia; 3) the additional growth of surface
V type centers due to photoadsorption of oxygen on surface F type centers and vice versa the
increasing V centers under illumination in hydrogen compared with illumination in vacuo [2,3]
are approximately ten fold higher for nano sized particles than for micro sized ones. The spectral
dependencies and the values of the quantum yields of studied photoprocesses are similar for both
types of zirconia samples.
The obtained results are treated on the base of the model of photocatalyst particle [4] in which
the efficiency of active centers formation is determined by the dimensionless rations of
parameters such as the particle size d, the inverse absorption coefficient α-1 for particle
substance, and diffusion length L for UV induced electrons and holes.
References
1. Gerihcher H. // Electrochimica Acta. -1993.- Vol.38. - No. 1. - P. 3 - 9.
2. Emeline A.V., Kataeva G.V., Ryabchuk V.K., Serpone N. // J. Phys.Chem. B. - 1999. Vol.103. - No 43. - P. 9190 - 9199.
3.
Emeline A.V., Sheremetyeva N.V., Khomchenko N.V., Kuzmin G.N., Ryabchuk V.K., Teoh
W.Y., Amal R.// J. Phys. Chem. C. - 2009. -Vol. 113. - No 11. - P. 4566 - 4583.
4. Emeline A.V., Ryabchuk V.K., Serpone N //J. Phys. Chem. B. - 1999. - Vol. 103. - No. 8. P. 1316 - 1324.
154
DECAY TIME OF ACTIVE SURFACE CENTERS
ON WIDE BAND GAP METAL OXIDES
V.K. Ryabchuk1, A.V. Emeline1, G.V. Kataeva2, N.V. Sheremetyeva1
1 – V.A. Fock Institute of Physics, St.Petersburg State University, Russia
2 – Faculty of Natural Sciences, Dimitrovgrad Subdivision of Ulianovsk State University, Russia
ryabchuk@photonics.phys.spbu.ru
Two sorts of photo induced active surface centers for wide band gap (Eg ≥ 3 эВ) oxide
photocatalysts distinguishing by decay time, had been considered early [1]. The first type of so
called short live active centers referred to surface shallow traps for photo carriers with decay
time within 0,1 – 0,001 s range. The second type of active centers (long-live centers of postsorption) considered as color centers-like deep thermally stable traps with indefinitely long
decay time at ambient conditions.
The results of mechanistic studies of different physical pathways of deactivation for active states
of centers on the surface of wide band gap oxides are presented here. It has been shown that the
given color centers-like surface centers with trapped carriers decaying via recombination with
photo carriers of opposite sign manifest themselves as short-live centers under illumination. At
the same time, these centers behave as long live centers of post-sorption on pre-irradiated in
vacuo wide bang gap oxides in the dark. The decay time of the centers under continued
illumination depends on intensity of actinic light. Thus, the dependence of photoadsorption rate
on gas pressure and on light intensity follows formally to Langmuir-Hnshelwood kinetics at
constant light intensity only. Typically the so called Langmuir constant depends inversely on
actinic light intensity in a case of linear photo carriers recombination for a given wide band gap
photo catalyst.
It has been demonstrated by means of recombination photodesorpton studies and by
photoadsoption kinetics numerical simulations that recombination cross section of active surface
centers drastically reduces when they transform into adsorption complexes (the center + photo
adsorbed molecule + trapped carrier) at chemical stage of photoadsorption. The latter is the
reason of reducing of so called “post-sorption coefficient” with increasing of irradiation time
established for a series of wide band gap oxides [1]. In addition, the same above mentioned
reduction of the recombination cross section leads to changing in a number of color centers of V
and F type created by actinic light due to photoadsorption, compared with that created under
illumination in vacuo at the surface and in near-surface area in micro- and nanoparticles of wide
band gap oxides [2].
The similar manifestations of recombination decay of active centers and intermediates for a case
of photo oxidation of phenols over titania photo catalyst in aqua are also discussed.
References
1. Solonitzyn Yu.P., Prudnikov I.M., Yurkin V.M. // Russ. J. Phys. Chem. - 1982. -Vol.57. –
No. 8. - P. 2028 - 2030.
2. Emeline A.V., Kataeva G.V., Ryabchuk V.K., Serpone N. // J. Phys.Chem. B. - 1999. Vol.103. - No 43. - P.9190-9199.
155
STRUCTURE AND PHYSICO-CHEMICAL PROPERTIES
OF PHOTOACTIVE SUPRAMOLECULAR SYSTEMS BASED
ON CROWN-CONTAINING OLIGOTHIOPHENE DERIVATIVES
S.L. Selector1, V.V. Arslanov1, O.A. Fedorova2, E.V. Lukovskaya2,
A.V. Bobyleva2, N.A. Tarasova1, Y.V. Fedorov3, O.A. Raitman1, A.V. Anisimov2
1 - IPCE RAS
2 - Chemistry Department of MSU
3 - IOEC RAS
pcss_lab@mail.ru
Electronic and optical properties of oligothiophenes with various covalently attached functional
groups facilitate their use in electroluminescent devices, sensors, solar cells, organic laser diodes
and field effect transistors. This research is devoted to comparison of structure and properties of
ultra thin films of two tristhiophene molecule geometric isomers bearing crown-styryl fragments
(I, II). Their supramolecular assemblies were obtained by two different ways: by complex
formation with Ba(ClO4)2 salt in organic solution and by Langmuir-Blodgett (LB) film
formation.
I
coordination
interaction
binding center
O
S
O
O
O
S
O O
O O O
O O
O O O
O
O
O
S
S
S
O
O
O
O
O
intramolecular
complexing
O
O
O
O
O
O
S
Ba
O
O
S
S
O
isomerisation at
air/water interface
O
O
S
S
air
water
S
O
O
O
S
Scheme 1
O
O
O
O
O
O
O
J-aggregate staking in LB film
S
S
S
S
S
stacking interaction
in LB film
O
O
+2
O
O
O
O
O
S
O
O
S
O
stacking interaction
under complexing
optical, electrochemical unit
II
O O
O O
O O
O
O O
S
S
O
O
O
O
O
By means of quite a number of different physico-chemical methods it was established that the
molecular structure influences substantially on the supramolecular organization (Scheme 1). As
it was shown earlier in the presence of barium perchlorate in an organic solvent compound I
forms the H-aggregate mode sandwich barium complexes. These supramolecular complexes are
inflorescence and inactive in photoisomerization reaction. The electronic absorbance spectra of
compound I LB films showed the significant blue shift of the main band, which indicates the
intense H-aggregate formation. On the other hand compound II forms intramolecular sandwich
complex in organic solutions of barium perchlorate (scheme). The addition of metal ions forces
the styryl fragments to change their position from anti- in free ligand to syn- in sandwich
complex. The red shift of both absorbance bands in compound II LB film spectra was recorded.
The generation of J-aggregates composed of similar syn-conformers is mostly probable for
compound II in LB films. Moreover by use of the in situ fiber-optic UV-spectroscopy
measurements it was shown that aggregate formation in Langmuir films takes place directly
during monolayers compression. The reversibility of such aggregation was established: the
decompression (expansion) of the monolayer restores its monomer state. The substantial effect of
the aggregate type on the electrochemical and optical behavior of two geometric isomer LB films
was demonstrated and discussed.
156
DETERMINATION OF MAGNETIC-DIPOLE TRANSITION 5D0 – 7F1
PURITY IN EUROPIUM CHLORIDE LUMINESCENCE IN SOLUTION
BY ENERGY TRANSFER TO DYES
T.A. Shakhverdov
St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
teimur@soi.spb.ru
Recently interest to so-called “photon metamaterials” [1] has increased. Meanwhile, their
properties, in particular negative refraction, can be reproduced with use magnetic-dipole
transitions (MDT) of lanthanide ions [2, 3]. However purity of such transitions remains
practically not studied. We define an admixture electric dipole transition (EDT) in radiative 5D0
→ 7F1 MDT of europium chloride in heavy water by energy transfer to dyes. The mechanism of
such energy transfer has been studied for the first time by us in works [4–6]. Later these works
have received the further advancement in connection with problems of biology [7–9] and
nanophotonics [10]. For definition of contribution EDT in MDT it has been used more than 20
dyes of triphenylmetane, thiazine, оxazine and other classes with absorption spectra in various
degree overlapped both with MDT, and with EDT of Eu(III) in radiation. Measurements are
carried out by means of Eu(III) luminescence lifetime quenching. It was expected, that
contribution 5D0 → 7F2 EDT in 5D0 → 7F1 MDT Eu(III) as a result of mixture of levels 7F1 and
7
F2 will not exceed 10 %. However it may be as much as 20 ± 10 %. Influence of the size of dyes
and their aggregation on the received results is discussed.
References:
1. M.M. Litchiniter, V.M. Shalaev, Laser Phys. Lett. 5 (2008) 411.
2. Q. Thommen, P. Mandel, Opt. Lett. 31 (2006) 1803.
3. N. Noginova, G. Zhu, M. Mavy, M.A. Noginov, J. Appl. Phys.103 (2008) 07E901.
4. V.L. Ermolaev, T.A. Shakhverdov, Opt. Spectrosc. 30 (1971) 515.
5. T.A. Shakhverdov, V.L. Ermolaev, Оpt.i Spectrosk. 33 (1972) 941.
6. Т.A. Shakhverdov, E.N. Bodunov, Opt. Spectrosc. 34 (1973) 646.
7. C.F. Meares, L.S. Rice, Biochemistry. 20 (1981) 610.
8. T. Yamamoto, S. Nakayama, N. Kobayashi et al., J. Mol. Biol. 241 (1994) 714.
9. K. Blomberg, P. Hurskainen, I. Hemmila, Clin. Chem. 45 (1999) 855.
10. S.S. Dudar’, E.B. Sveshnikova, V.L. Ermolaev, Opt. Spectrosc.104 (2008) 724.
157
COMPARATIVE STUDY OF SPECTRAL PROPERTIES OF CROSSCONJUGATED BISAMINOKETONES AND DINITRILES
L.A. Shvedova1, A.S. Tatikolov1, Zh.A. Krasnaya2
1 – N.M. Emanuel Institute of Biochemical Physics RAS, Moscow, Russia
2 - N.D. Zelinsky Institute of Organic Chemistry RAS, Moscow, Russia
shvedova@sky.chph.ras.ru
The spectral-fluorescent properties of a set of dye molecules (ketocyanines – polyenic bis-ω,ω'aminoketones, and their analogues – dinitriles containing a dicyanomethylene fragment instead
of the carbonyl group) was investigated in solvents of different polarity and ability for specific
and nonspecific solvation.
ketocyanines
dinitriles
NC
O
β
δ
Me2N
α
α'
β'
γ
δ
β
γ
Me2N
β
CN
δ'
β'
γ'
NMe
β
δ
Me2N
β'
α'
α
α
NMe2
CN
α'
δ'
β'
γ
NC
δ'
γ'
γ
NC
α'
α
δ
NMe2
γ'
O
Me2N
δ'
γ'
NMe2
CN
O
Me2N
NMe2
Me2N
NMe2
The absorption spectra of dinitriles are shifted bathochromically with respect to the spectra of
corresponding ketocyanine dyes. This can be explained by elongation of the chromophore chain
by one double bond in dinitrile molecules. Based on the solvatochromic shifts of the absorption
and fluorescence spectra, the specific and nonspecific solvation of dinitriles and corresponding
ketocyanies was studied. The photophysical data obtained for the examined molecular structures
were correlated with different empirical parameters, which characterized solvation ability of a
solvent: the Dimroth–Reichardt parameter ET(30), the acceptor number AN, the donor number
DN, and the parameter π* for characterization of solvent polarity/polarizability. For ketocyanines
under investigation a linear correlation is observed between the wavenumbers of the absorption
maxima and the acceptor number AN characterizing the specific solvation. It is confirmed that in
the ketocyanie solutions the electrophilic solvation plays a main role. For dinitriles a linear
correlation for the wavenumbers of the absorption maxima was obtained as f(π*, AN, DN). In
this case a significant contribution of nonspecific and nucleophilic solvation is observed in
addition to electrophilic solvation.
158
DECAY KINETICS OF TRIPLET STATES AND RADICALS OF FLAVINS
IN THE BOVINE LENS STUDIED BY LASER FLASH PHOTOLYSIS
A.S. Tatikolov1, P.P. Levin1, N.B. Sultimova1, I.G. Panova2
1 - N.M. Emanuel Institute of Biochemical Physics RAS, Moscow, Russia
2 - N.K. Koltsov Institute of Developmental Biology RAS, Moscow, Russia
tatikolov@sky.chph.ras.ru
The mammalian lens represents the complex aqueous colloidal system generally consisting of
proteins named crystallins. Its content can reach values up to 70% of the total mass of the biotissue. The interaction between crystallins is one of the reasons for their ordering, which seems
to be important for the lens transparency, and this nanoscale ordering affects physical microparameters of protein medium. The microcharacteristics of the lens medium, in particular,
peculiarities of molecular diffusion, were studied by various methods such as dynamic light
scattering and kinetic experiments with fluorescent probes. Riboflavin seems to be an interesting
kinetic photochemical probe of natural protein media since it is present in the lens and probably
assists its photodegradation. Riboflavin and its derivatives, for example, flavin mononucleotide,
absorbing light in the visible region, are efficient photosensitizers of oxidation processes. It is
supposed that the studies of kinetic behavior of flavin triplet states and radicals directly in the
lens medium can give new information about its structure and microcharacteristics.
In the present work the kinetics of fast reactions of riboflavin (RF) and flavin mononucleotide
(FMN) were studied by the laser flash photolysis technique in bovine lens (L) and its aqueous
solutions.
The photoexcitation of aqueous solutions of Rf and FMN at neutral pH results in the formation
of the triplet excited states of riboflavin (3Rf) and flavin mononucleotide (3FMN). The addition
of L results in the acceleration of 3Rf and 3FMN decay and the formation of corresponding RFH•
and FMNH• (рКа = 8.3) radicals.
It was found that the rate constant of radical decay only slightly increased in the course of L
dilution by water up to 50%, but then the sharp acceleration of radical decay is observed after
further dilution above 50%. It seems that such behavior can be explained in terms of the
variations of the protein medium nanostructure. The dependence obtained correlates well with
the data on light scattering.
At the same time it was shown that, in spite on high apparent viscosity, the kinetics of RfH• и
FMNH• radicals decay in aqueous solutions of collagen and hyaluronic acid, or in the hen eggwhite, is similar to that in water. The effects of globulation and nanostructural features of protein
media on reaction kinetics of small probe molecules are under the discussion.
The financial support from the Russian Foundation for Basic Research (project 09-04-01054a)
is acknowledged.
159
FLUORESCENCE RESONANCE ENERGY TRANSFER
AND COMPLEX FORMATION BETWEEN CYANINE DYES AND DNA
A.S. Tatikolov, P.G. Pronkin
N.M. Emanuel Institute of Biochemical Physics RAS, Moscow, Russia
tatikolov@sky.chph.ras.ru
Noncovalent interaction of dyes and related compounds with various biomacromolecules has
been the subject of numerous studies, since it forms the basis for occurrence in vivo of a variety
of photochemical processes [1] and, thus, makes it possible to use dyes both in biomedical
studies as DNA labels and in clinical practice [2, 3]. In this respect, polymethine (cyanine) dyes
are of particular interest [4]. Owing to the high sensitivity typical for fluorescent analytical
techniques, fluorescence resonance energy transfer (FRET) attracts the rapt attention of
researchers [5 – 8].
In the present work FRET was studied between carbocyanine dyes in noncovalent complexes
with DNA. A DNA molecule used as a rigid matrix for the dye molecules embedded, which
facilitated the energy transfer due to the drawing together the molecules of the donor and
acceptor dyes. Polymethine dyes 3,3'-9-triethyl-5,5'-dimethyloxacarbocyanine iodide (donor) and
3,3'-diethylthiacarbocyanine iodide (acceptor) were used for the intermolecular FRET
investigation in complexes with DNA. The experiments were carried out in a wide range of
DNA concentrations (10–6 – 5 x 10–4 M).
It was found that in the range of low concentrations of the biopolymer (< 5 10–5 M) the FRET
efficiency (r) remained constant (0.44 ± 0.01). The subsequent increase in the DNA
concentration led to a decrease in r (to 0.23 ± 0.02, cDNA = 4.9 x 10–4 M). The experimental data
were interpreted in terms of both the dye–DNA stoichiometric complex and the pseudophase
model. The latter model was shown to describe adequately the experimental results.
[1] A.N. Glazer, H.S. Rye. Nature 359 (1992), 859.
[2] E.S. Voropay, M.P. Samtsov, A.P. Ludovsky, A.N. Sevchenko. Proc. SPIE – Int. Soc. Opt.
Eng. 4749 (2004), 221.
[3] B.P. Matselyukh, S.M. Yarmoluk, A.B. Matselyukh, V.B. Kovalska, I.O. Kocheshev, D.V.
Kryvorotenko, S.S. Lukashov. J. Biochem. Biophys. Methods 57 (2003), 35.
[4] E. Delaey, F. van Laar, D. De Vos, A. Kamuhabwa, P. Jacobs, P. de Witte. J. Photochem.
Photobiol. B: Biol. 55 (2000), 27.
[5] Laib S., Seeger S. J. Fluoresc. 2004. V. 14. P. 187 – 191.
[6] Bunkenborg J., Gadjev N.I., Deligeorgiev T., Jacobsen J.P. Bioconjug. Chem. 2000. V. 11. P.
861 – 867.
[7] Bunkenborg J., Stidsen M.M., Jacobsen J.P. Bioconjug. Chem., 1999. V. 10. P. 824 – 831.
[8] Clegg R.M., Murchie A.I.H., Zechel A., Lilley D.M.J. Proc. Natl. Acad. Sci. USA. 1993. V.
90. P.2994 – 2998.
160
REACTIONS OF PHOTOINDUCED AND THERMAL
RECOORDINATION IN OPTICAL MOLECULAR SENSORS
E.N. Ushakov1, S.N. Dmitrieva2, A.I. Vedernikov2, L.G. Kuz’mina3,
A.Ya. Freidzon2, M.V. Alfimov2, S.P. Gromov2
1 - Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
2 - Photochemistry Center RAS, Moscow, Russia
3 - N.S. Kurnakov Institute of General and Inorganic Chemistry RAS, Moscow, Russia
en-ushakov@mail.ru
Interest in the reactions of recoordination in the complexes of metal cations with the ligands
having a donor-acceptor chromophore arose in the connection with the development of optical
molecular sensors [1–3]. The photoinduced disruption of coordination bonds in the complexes
involving ionochromic azacrown compounds is most widely investigated.
The mechanism of the photoinduced recoordination is not yet clearly understood. In some works
it is asserted that the photoinduced disruption of the N---Mn+ coordination bond is followed by
the complete dissociation of the complex, i.e. the metal cation is released from the macrocycle
cavity into solution during the excited state lifetime [4]. However, this interpretation in some
cases disagrees with the known data on the kinetics of complex formation reactions.
Previously we supposed that the complexes of some ionochromic crown compounds with metal
cations can undergo the recoordination reaction not only in the excited state but also in the
ground state [5].
That is the complex of 1:1 composition in the ground state can exist as two thermodynamically
equilibrated forms (like А and В in the scheme). However, until recently there were no solid
experimental evidences for this hypothesis.
In this report we will discuss the mechanisms of photoinduced and thermal recoordination, as
well as the kinetic aspects of cation–macrocycle interactions. In addition, new experimental data
will be presented that conclusively prove the possibility for the thermal recoordination to occur
in the complexes involving ionochromic crown compounds.
This work was supported by the Russian Foundation for Basic Research and RF Ministry of
Science and Education.
Literature:
[1] M.M. Martin et all, Chem. Phys. Lett., 1993, 202, 425-430;
[2] P. Dumon et all, J. Phys. Chem., 1994, 98, 10391-10396;
[3] V. Van den Bergh et all, Biophys. J., 1995, 68, 1110-1119;
[4] C. Ley et all, ChemPhysChem, 2009, 10, 276-281;
[5] E.N. Ushakov et all, Izv. AN, Ser. Khim., 1997, 484-492.
161
INFLUENCE OF THE SOLVENT ON THE RADIUS
OF ELECTRON-EXCHANGE INTERACTIONS
0
OF d METAL COMPLEXES WITH CYCLOPENTADIENE
V.P. Vasiliev, G.V. Loukova, V.A. Smirnov
Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
vpvasiliev@mail.ru
A great number of chemical reactions and interactions occur in solutions, therefore one of most
important problems is resolution of relationship between chemical reactivity and medium
properties, solvent effects, and pairwise solvent – solute interactions. Earlier, we demonstrated
that triplet – triplet radiationless energy transfer from metallocenes Cp2MCl2 (M = Zr, Hf) to
catalysts substrates (olefins and/or dienes) in glassy solutions, made of non-specific solvent
methylcyclohexane, can be well described in terms of the Perrin equation viz. Ф0/Ф =
exp(N·V·[A]) (where Ф0 and Ф denotes the emission quantum yield in the absence and in
presence of the emission quencher, V stands for the volume of a quenching sphere of the radius R
(in cm), N = 6.02·1020, and A is the emission quencher concentration).
In the present work, influence of a solvent on effectiveness of electron-exchange resonant energy
transfer from d0 organometallic complexes to non-phosphorescing cyclopentadiene was studied
in glassy organic solvents at 77 K. It should be noted that concentration dependences of
phosphorescence quenching of metallocene complexes Zr and Hf in glassy media obey well the
Perrin equation. Radius of radiationless energy transfer was revealed to be affected by solvation
of the metal complexes of the studied series. Thus, for instance, the critical radius of electronexchange energy-transfer sphere drastically decrease (for 2–3 Å, i.e. for 15–20%) with enhance
in the energy-donor solvation effectiveness upon other equal conditions. Besides, dependence of
R0 on solvent properties remains the same on going from hafnium to zirconium complexes and
upon the ligand sphere modifications. Interestingly, values of the critical radius of triplet – triplet
energy-transfer sphere are virtually the same (within the error limits for R0), regardless the
difference in transition metal ion (Zr or Hf) in isostructural complexes. In summary, the results
obtained allow us to assume that the critical radius of triplet – triplet energy-transfer sphere
appers to be quite sensitive toward changes in the composition of solvent shells around
photoexcitation energy-donor molecules.
Acknowledgements. The authors express their gratitude to Professor A.E. Shilov for fruitful
discussion and Dr. W. Huhn («Procter & Gamble Italia») for a kind loan of single-crystalline
samples of rac-С6H10(IndH4)2ZrCl2. This work was financially supported by Russian Academy of
Sciences and Russian Foundation for Basic Research (project N 09-03-00379).
162
FTIR EVIDENCE FOR LEWIS ACIDITY INDUCED BY ADSORPTION
K.V. Voronina, A.A. Tsyganenko
V.A.Fock Institute of Physics, St.Petersburg State University, Russia
tsyg@photonics.phys.spbu.ru
Strength of surface sites of oxide catalysts is known to depend on the presence of dopants or
preadsorbed molecules. Brønsted acidity of silanol groups of silica was shown to increase after
adsorption of such acids as CO2 or H2S, and addition of SO2 or NO2 even leads to protonation of
coadsorbed bases, such as ammonia, pyridine or 2.5-dimethylpyridine (DMP)1. The same effect
of induced Brønsted acidity was observed for alumina2 and magnesia3 exposed to H2S. On the
other hand, basicity of oxygen atoms of silanol groups measured by adsorbed fluoroform,
increases greatly in the presence of bases4. One could anticipate that interaction of acidic
molecules with surface oxygen ions linked to the cations should just the same affect the Lewis
acidity of the latter. To check up this supposition we have studied the influence of CO2 and SO2
adsorption on the acidity of CaO, using low temperature CO adsorption as a test.
CO adsorption on pure CaO outgassed at 973 K results in the bands of ”carbonite” CO22- ions5
together with the bands of molecularly adsorbed carbon monoxide at 2155-2165 cm-1. No other
bands were detected at higher wavenumbers. However, if the sample is pre-exposed to CO2, the
carbonite bands do not appear and the band of molecularly adsorbed CO shifts up to 2179 cm-1
while after preliminary adsorption of SO2 the highest position of this band at low coverages
reaches 2184 cm-1. So high frequencies can hardly be explained by interaction with OH groups.
Interaction with the most acidic hydroxyls of zeolites shifts CO band up to 2175 cm-1 only6.
Unlike MgO3, CO adsorption on CaO pre-exposed to CO2 or SO2 is not accompanied by OH
band perturbation and adsorption of DMP does not lead to characteristic bands of protonated
base molecules. For CaO outgassed at 773 K or exposed to H2O at 300 K surface concentration
of OH groups is much higher, however, after adsorption of CO2 or SO2 the intensity of the highfrequency CO bands is lower that for the sample treated at 973 K. Thus, we assign the highfrequency CO band to molecules coordinately bound to surface cations, whose electronaccepting ability is enhanced as a result of CO2 or SO2 adsorption.
Effect of weakly adsorbed electron-accepting molecules upon the strength of cationic sites can
be explained as a result of electron density shift from the cation towards the molecule. In our
case chemisorbed CO2 or SO2 exist in the form of surface carbonate or sulfite ions, and one can
even consider the surface as a layer of corresponding salt. The results, thus, infer higher electron
accepting ability of cations in salts as compared with oxides. In the electrostatic model the
increased frequency shift of adsorbed CO reflects the higher electrostatic field of the cation
surrounded by larger anions when O2- ions are transformed to CO32-, etc. This effect is consistent
with superacidity of zirconia doped with SO42- anions7. The highest acidity, close to that of
naked cations, is not by chance observed for cationic zeolites, where the negative charge is
distributed over the whole polyanionic alumosilicate framework. CO adsorption on such systems
reveals linkage isomerism9, which could be, thus, also anticipated for salts or oxide surfaces
modified by adsorption of acids. Experiments for the search of this effect are in progress.
The work was supported by RFFI, grant 06-03-32836a.
References:
[1] Tsyganenko A.A., Storozheva E.N., Manoilova O.V. Catal. Today, 70 (2001) 59.
[2] Travert A., et al. J. Phys. Chem. B, 106 (2002) 1350.
[3] Oliviero L., et al. Industrial & Engineering Chemistry Research., 48 (2009) 1237
[4] Storozheva E.N., Sekushin V.N., Tsyganenko A.A. Catal. Letters. 107 (2006) 185.
[5] Babaeva M.A., Bystrov D.S., Kovalgin A.Yu., Tsyganenko A.A. J. Catal., 123 (1990), 396.
[6] Otero Areán С., et al. Eur. J. Inorg. Chem., 2001, 1739.
[8] Ivanov A.V., Kustov L.M. Rossijskij Khimicheskij Zhurnal. 44 (2000) 21.
[9] Otero Areán C., Turnes Palomino G., Tsyganenko A.A., Garrone E. Intern. J. Mol. Sci., 3 (2002) 764.
163
SYMPOSIUM
“FUNDAMENTAL PRINCIPLES OF NANOPHOTONICS”
ORALS
OBTAINING, PROPERTIES AND PERSPECTIVES
OF COLLOIDAL QUANTUM DOTS
S.B. Brichkin, M.G. Spirin, D.Yu. Nikolenko, V.Yu. Gak, V.F. Razumov
Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
brichkin@icp.ac.ru
Quantum dots (QD) are nanoobjects which optical and electronic properties depend on their size
because of quantum confinements for charge carriers. QD are perspective for wide practical
applications in solar sells, light emitting diodes, optical sensors, lasers, elements of optical memory,
medicobiological diagnostics et al. In this report the results of experimental investigations of
different size effects in semiconductor QD and metal nanoparticles (NP), obtained by methods of
micellar and high temperature colloidal synthesis are represented.
The formation of NP in reverse micell solutions (RV) occurs in water pools and is controlled by
intermicellar exchange. Water pools are nanoreactors, in which particles are formed, and micellar
shells stabilize them. The NP size can be governed by changing the water pool size. Different NP
both of individual (AgHal, CdS, CdSe, RuS2, γ-Fe2O3) and complex compositions were obtained by
using this method.
At the formation of NP with core-shell structure (AgBr@AgI) it was established that in the case of
epitaxial growth the affinity of crystal structures of core and shell is of great importance. At the
synthesis of β-AgI NP the effect of water structuring was found.
The formation of NP in RV is substantially defined by the permeability of micellar shells, which
strongly depends on the hydrocarbon chain length of the organic solvent. Hydrocarbons with short
chain more efficiently slow down the rate of NP growth, and in large micelles molecules of
hydrocarbon solvent penetrate into micellar shell better. The methods of NP size stabilization were
developed.
At the synthesis of gold NP it was shown that by changing of experimental conditions (surfactant or
reducing agent type) it is possible to vary considerably the size features of NP, and to obtain not only
spherical particles of different size and size distribution, and also NP of anisotropic shape.
In the method of high temperature colloidal synthesis we proposed a new approach to realization of
the NP size distribution “focusing” regime by controllable temperature reducing. By using this
approach CdSe, CdTe NP of different sizes with tunable spectral properties were obtained, and coreshell NP CdSe@ZnSe with high luminescent efficiency (up to 60%) were synthesized.
New effective technique for synthesis of CdSe NP with high yield of tetrapod shape without any
additional size and shape selection was developed.
The availability of “spin- coating” method for the formation of ordered monolayers of polystyrene
latex particles (LP) was shown. The sizes of ordered domains reached several hundreds of
nanometers, and LP in the ordered domains were packed in cubical or hexagonal lattices, with
structure of grooves and dimples. This structure was used for the ordering of spherical silver NP
(dср=20 nm) into the linear chains. Such ordering results in cardinal changes in absorption spectrum
of ordered silver NP in comparison with spectrum of free state silver NP, in solution. The technique
of controllable etching of ordered LP monolayers in the oxygen plasma was realized. This method
opens up extensive possibilities for nanolithography.
This work is financially supported by Program of Fundamental Research RAS №27 “Basic
fundamental research in nanotechnology and nanomaterials”, and Russian Foundation for Basic
Research (project № 07-03-00397).
164
SEMICONDUCTOR QUANTUM DOT MOLECULE
PHOTOLUMINESCENCE MEDIATED BY
INCOHERENT REVERSIBLE ENERGY TRANSFER
A.V. Fedorov, A.V. Baranov, S.Yu. Kruchinin, A.V. Savelyeva, M.V. Mukhina
St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
a_v_fedorov@inbox.ru
One of the basic problems of low-dimensional physics is the energy transport of elementary
excitations in nanostructures and particularly the nonradiative energy transfer between
semiconductor quantum dots (QDs). The problem is especially important for one-, two-, and
three-dimensional structures with enough close-packed arrangement of QDs, i.e. when an
interdot distance is equal in order of value or less than the QD size. Among such structures are
the quantum dot molecules, chains, rings, two- and three-dimensional arrays as well as the
dendrites based on QDs. For small interdot distances the interaction between QD electronic
subsystems becomes the governing factor determined a lot of physical properties of QD
ensembles. The interaction can lead to both the incoherent and coherent processes of energy
transfer between QDs. Presence or absence of the coherent effects in energy transfer from a QDdonor of energy to a QD-acceptor of energy is determined by the relation between the transfer
rate γ DA and the dephasing rate ΓDA for this transition. If ΓDA >> γ DA , then the incoherent energy
transfer takes place; otherwise the coherent effects will influence essentially on the energy
transport between QDs. For incoherent energy transfer it should be separated two cases that
differ from each other by the relation between γ DA and the intraband energy relaxation rate γ A
for QD-acceptor. If γ A >> γ DA , then the energy transport will be irreversible. If γ A is equal in
order of value or less than γ DA , then some portion of the energy will come back from the QDacceptor to the QD-donor. Experimental data [1-4] show that γ A can vary in value from 108 s-1
to 1013 s-1. Since γ DA may be as much as 1012 s-1 [5] it should be expected that both the
incoherent reversible and coherent energy transfer can be realized for real QD systems. Hence an
investigation of both the processes is problem of current importance.
Energy transfer should be manifested for optical spectra of interactive QDs. It has been observed
for QDs of different types in the photoluminescent experiments in frequency and time domains.
Despite a lot of theoretical works devoted study of different aspects of energy transport in QDs,
the consistent description of QD secondary emission spectra taking into account the energy
transfer process has not been developed up to now. In present work based on our previous results
[5] the theory of stationary photoluminescence for semiconductor quantum dot molecule with the
incoherent reversible energy transfer is developed and the essential features of corresponding
spectra allowing to distinguish the energy transfer regimes using experimental data are
discussed.
1. C. Bonati, A. Cannizzo, D. Tonti, Phys. Rev. B 76, 033304 (2007).
2. P. Guyot-Sionnest, B. Wehrenberg, D. Yu, J. Chem. Phys. 123, 074709 (2005).
3. K. Ikeda, H. Sekiguchi, F. MinamiIkeda, J. Lumin. 108, 273 (2004).
4. R. Heitz, H. Born, F. Guffarth, et al., Phys. Rev. B 64, 241305 (2001).
5. S.Yu. Kruchinin, A.V. Fedorov, A. V. Baranov et al., Phys. Rev. B 78, 125311 (2008).
165
MOLECULAR DESIGN OF LIGHT-SENSITIVE NANOSIZED SYSTEMS
BASED ON UNSATURATED AND MACROCYCLIC COMPOUNDS
S.P. Gromov1, E.N. Ushakov2, A.I. Vedernikov1, L.G. Kuzmina3, M.V. Alfimov1
1 - Photochemistry Center RAS, Moscow, Russia
2 - Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
3 - N.S. Kurnakov Institute of General and Inorganic Chemistry RAS, Moscow, Russia
spgromov@mail.ru
A new trend is being currently formed in nanotechnology, namely, organic nanophotonics.
We propose a new unique class of polyfunctional light-sensitive compounds: crown-containing
unsaturated dyes functioning as photochromes, fluorophores and ionophores. A large body of
research has been performed for their synthesis, determination of their spatial structures, study of
self-assembly features to give nanosized systems, and also study of fluorescent, photochemical
and complexing properties.
Resulting from the research, we elaborated for the first time universal molecular meccano,
allowing one to accomplish building-up, with using a limited number of complementary
compounds, light-sensitive and light-emissive nanosized systems of varied architecture with
adjusted properties. Within the same class of compounds one can construct in solution, solid and
at the air-water interface new types of molecular switches, photocontrolled molecular machines,
photosensitive monolayers and monocrystals susceptible to all of the key photoprocesses.
hν
M n+
displacement
hν
PHOTOANTENNA
PHOTOANTENNA
CROWN
cucurbituril
molecular devices
molecular machines
The high practical value of these studies deserves attention. They provide a new strategy for the
design of materials for nanophotonics, which was demonstrated, first of all, by the creation of
practically important sensor and photochromic materials.
This work was supported by the Presidium and the Division of the RAS, the Ministry of Science
and Education, the Russian Foundation for Basic Research, the Moscow Government, the
INTAS, the CRDF and International Science Foundation (ISF), the DFG, and the Royal Society.
166
AOT/WATER/HEXANE REVERSE MICELLES AS “MICELLAR SIEVES”
FOR CYANINE DYE J-AGGREGATES
A.V. Ivanchikhina1, L.M. Nikolenko2
1 - Moscow Institute of Physics and Technology
and Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
2 - Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
Ivanchihina@gmail.com
During the past decade J-aggregates have attracted the interest of several research groups, due to their
peculiar structural and photophysical properties which make them potential candidates for applications in
nonlinear optics, nanometre-sized photoconductors and light harvesting systems. The preparation of
monodispersed nanometer-sized J aggregates is of great practical importance. One of possible ways of
solving this problem seems to be the use of reverse micelles.
We investigate the behavior of J-aggregates of a cyanine dye, 3,3’-di-(γ-sulfopropyl)-4,5,4’,5’-dibenzo-9ethylthiacarbocyanine betaine pyridinium salt, in AOT/water/hexane reverse micelles (W = 2–50), both
during the course of rapid microemulsion formation and then after stabilization of the microemulsions at
thermodynamic equilibrium.
We obtained the time evolution of the absorption spectra of DEC in micellar solutions for W varied over
the range 2–50.
The time-resolved spectra show that DEC is present in the form of J-aggregates already at the earliest
stages after mixing when the micellar structure has not yet been formed. After aggregation, some dye Jaggregates decompose into trans-monomers, and the fraction of such J-aggregates diminishes with
increasing W. Since in our experiments W was varied on change in the AOT concentration, it can be
inferred that the amount of monomers formed in the system grows with increasing [AOT] (decreasing W).
The absorption spectra of as-prepared solutions with different W show that with increasing W, the
intensity of the J-band is seen to grow while that of the M-band, to decrease.
The temporal behavior of J-aggregates in the micellar system also depends on W. The observed spectral
changes can be related only to precipitation of J-aggregates. The amount of precipitated aggregates
diminishes with increasing W.
The obtained data enabled us to explain (for the first time) the formation mechanism of the J-aggregates
of cyanine dye in micellar solution and their temporal behavior. The processes defining the above
dependencies were found to take place prior to attaining equilibrium in microemulsion and are as follows:
Formation of J-aggregates in the aqueous macrophase;
Deaggregation of J-aggregates on interaction with AOT molecules penetrated into the aqueous
macrophase. The AOT molecules already built-in into the micelle shells (which is typical of stable
microemulsions) cannot cause the deaggregation;
Encapsulation of the J-aggregates (by RMs) whose sizes are smaller than those of water pools and
displacement of larger aggregates into the organic phase where they get gradually consolidated and then
precipitated.
In view of this, micellar solution can be compared with a sieve for selection (i.e., by leaving in suspended
state) and stabilization of aggregates with a desired size, the value of W defining the upper size limit for Jaggregates that are sifted out by the micellar sieve.
It was shown that the only possible way to introduce dye into micellar solution through the aqueous phase
(even at elevated temperatures) fails to distribute dye monomers among micelles with subsequent Jaggregation via intermicellar exchange. This is because the J-aggregates of cyanine dye are formed in the
aqueous macrophase prior to formation of RMs. Hence the mechanism based on intermicellar exchange
and applicable to formation of inorganic nanoparticles and porphyrin J-aggregates is inapplicable to the
system under study.
This work is financially supported by Program of Fundamental Research RAS №27 “Basic
fundamental research in nanotechnology and nanomaterials”.
167
DELAYED FLUORESCENCE ANNIHILATION KINETICS CHANGE
BY RECONSTRUCTION OF POLYMERIC CHAIN STRUCTURE IN
SOLID SORBENT CAVITIES AND ON NANOPARTICLE SURFACES
M.G. Kucherenko, S.V. Izmodenova, N.Y. Kruchinin
Orenburg State University, Russia
rphys@mail.osu.ru
When some functional nanodevices building problems are appear, the macromolecule chain
conformation characteristics determination is required often in sorbent cavities or on disperse
nanoparticle surfaces. A polymeric chain, containing photoactive centres in its structure and
adsorbed by nanocavity walls is one of the perspective functional nanosystem. If molecules,
presenting itself such centres, adsorbed by the chain on its length uniform, the spatial distribution
behavior of their concentrations will repeat the density averaged profile of polymeric subunits.
The non-uniform molecules spatial distribution renders an essential influence upon a kinetic
mode formation of reactions with the molecule participation in the nanoarea. At the detailed
description of a photo-reactions kinetics in nanosystems and decryption of accompanying
luminescent signals it is necessary to take into account the radial profile of polymeric sections. In
this work we used an analytical expression that found earlier (Kucherenko M.G., Chmereva
T.M., 2008) for the spatial sections distribution of the polymeric chain, adsorbed by spherical
nanocavity walls. Another expression for the like distribution on surfaces spherical nanoparticle
is received. Besides, on example of 70-section lyzocime fragment a molecular-dynamic
modeling of the section density radial profile is realized for the comparison with analytical
dependencies. A mathematical model of the cross-annihilation kinetics of organic molecules
triplet (Т) excitations with molecular oxygen 1 ∆ g -excitations is offered for the cases of
nanopores and nanoparticle colloidal solutions with macromolecular chains "edge of a forest".
T∆
(t ) was defined on the base of the ТThe cross-annihilation delayed fluorescence pulse form I DF
centres concentration distribution nT ( r , t ) and the oxygen molecule excitation distribution
n∆ (r , t )
T∆
(t ) ~ ∫ nT (r , t )n∆ (r , t )4π r 2 dr .
I DF
∞
0
Time dependencies of the dye crossannihilation delayed fluorescence
T∆
(t ) in nanopores with
intensity I DF
different radius R
Satisfactory agreement between theoretical kinetic curves and experimental cross- annihilation
delayed fluorescence intensity signals of xantene dyes in porous sorbents is observed.
This work was supported by the Russian Foundation for Basic Research (project no. 08-0299035- r2006_ofi) and the Ministry of Education and Science of the Russian Federation
(assignment no. 1.3.06 from the Federal Agency of Education).
168
THE FEATURES OF THE RECOMBINATION PROCESSES
INTO THE PYROLYTIC CdS FILMS
T.L. Maiorova, V.G. Klyuev, M. Pham Thi Hai, V.S. Bikovskaya
Voronezh State University, Russia
mtl084@yandex.ru
Keywords: the photoconductivity, CdS, the photomemory effect
The subject of our investigations is the photoelectrical properties of the pyrolytic CdS films,
alloyed by alkaline metals. So there have been determinated that
1. the pyrolytic CdS films have enough high quantum yield of photoluminescence~ 1 % at
the room temperature;
2. the alloying of CdS pyrolitic films by alkaline metals results in the multiplying of
luminescence intensity by 3 ÷ 5 as against the pure ones;
3. the photoluminescence of such films are stable to influence of the ultraviolet irradiation
during long time;
4. the investigated structures have the long relaxation of photocurrency (the photomemory)
(t ~ 103 – 104 c) at room temperature.
The photomemory effect is due to inhomogeneous structure of the samples containing potential
barriers between low- and high-resistance regions. The latter debars the recombination of
nonequilibrium carriers.
The doping of alkaline metals, for example Cs, is due to the presents of Cs+i defects and the
increase of the number of V+S, Cl+S defects. In virtue of these the difference between low- and
high-resistance regions diminishes at large impurity concentration, the potential barrier
responsible for the stored photoconductivity decreases. At this the whole recombination is faster
then the one for the films with small concentration of the impurity, though it saves the character
of the stored photoconductivity.
By means of the thermally stimulated conductivity technique, information on the energy levels
of electron traps in pyrolytic CdS films was obtained. It has been shown, that the observed
thermal stimulated conductivity may be due to not only the present of the electron localization
levels, but their interaction with the potential barrier responsible for the stored
photoconductivity.
In the results of the recombination processes investigations, we have constructed the energy
model of the levels in the band-gap of the pyrolytic CdS films, alloyed by alkaline metals.
The observed properties are practically important for the using of the investigated structures as
solar cells, radiation sources or radiation detectors in devices designed to have stable parameters
in radiation fields. The results of the investigation allow to optimize the synthesis technology of
CdS pyrolytic films with controllable properties, in particular, for the use of such structure as
photomemory elements. Furthermore the pyrolytic CdS films are interested not only for the
applied aspect but for the fundamental investigations of the recombination processes into such
structures.
169
LUMINOPHORE-CONTAINING MONODISPERSE
POLYMERIC NANOPARTICLES: DESIGN, SELF-ASSEMBLING,
AND APPLICATION FOR CHEMISENSORICS
A.Yu. Menshikova1, N.N. Shevchenko1, T.G. Evseeva1, A.V. Yakimansky1,
V.A. Sazhnikov2, A.V. Koshkin2, M.V. Alfimov2
1 - Institute of Macromolecular Compounds RAS, St.Petersburg, Russia
2 - Photochemistry Center RAS, Moscow, Russia
asya@hq.macro.ru
Modern polymer science has developed methods to prepare monodisperse polymeric particles
from 30 nm up to 10 µm in diameter. These particles are of great interest for nanotechnology,
since their self-assembling from dispersions is a promising way to design of novel materials with
hierarchic structures. Thus, 3D-ordered arrays of submicron particles demonstrate photonic band
gap (PBG) in the spectral range of visible or near IR light, which are of importance for
optoelectronics. Moreover, in the ordered arrays built up by dye-containing uniform particles,
absorption or emission spectra remarkably changes in the PBG vicinity, which can be used in
various applications. The dye-containing particles can also serve as sensing elements, if dyes in
their surface layers ensure optical response to various analytes in contacting liquid or gas phases
due to their complexation with the dyes. Hence, there is a drive to develop new methods for
surface modification of monodisperse polymeric particles with dyes forming sensing sites.
Monodisperse polymeric particles were synthesized by heterophase copolymerization of styrene
and methacrylic acid and ion-exchange of cationic chromophores (Rhodamine 6G, Nile Red) on
the negatively charged particle surface was carried out. Poly(methyl methacrylate-co-Nvinylformamide) particles were prepared in the presence of β-cyclodextrin, which localized on
the particle surface and formed inclusion compounds with some dyes.
Besides, surface of poly(styrene-co-N-vinylformamide) particles were hydrolyzed, forming
aliphatic amino groups in N-vinylformamide units, which were used for Fluorescein
isothiocyanate covalent binding.
Alternatively, core-shell monodisperse particles were prepared by seeded dispersion
copolymerization, adding dye-containing comonomers along with cross-linkers at the last step to
incorporate them into particle shells. To enhance the selectivity of the interaction between dyes
and analytes, molecular imprinting technique was applied. For this purpose, seeds were swollen
with comonomers and a molecular template (methanol, ethanol, acetone, or toluene), removing
one after polymerization. This approach allowed generating robust and selective synthetic
receptors for recognition of small molecules in the particle surface layer.
Effects of the methods of dye incorporation on fluorescence spectra of particle arrays and their
changes in the presence of volatile analytes were revealed. Obtained results showed a good
promise of arrays built up with dye-containing polymeric particles as sensing elements for gas
chemisensors.
The work is supported by the Federal Agency on Science and Innovation of the Russian
Federation (contract 02.513.12.3025) and by the Scientific Program “Basic research of
nanotechnology and nanomaterials” of the Presidium of the Russian Academy of Sciences.
170
MOLECULAR DYNAMICS SIMULATIONS OF AN AOT
REVERSE MICELLES SELF-ASSEMBLY
A.V. Nevidimov
Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
nevidimovsasha@yandex.ru
Molecular dynamics is a powerful technique for investigation nanoscale molecular systems such
as biological molecules, nanoparticles, and polymers. In particular, molecular dynamics
simulations are employed to study reverse micelles structure in atomic detail. Reverse micelles
are formed in nonpolar solutions of certain amphiphilic molecules. Due to ability to dissolve
considerable water amounts reverse micelles are widely used in chemical and biochemical
catalysis as well as in narrow size distribution nanoparticles synthesis. The latter application is
because of narrow size distribution of reverse micelles themselves. At that the structure of the
reverse micelles defines the shape and size of nanoparticles synthesized, and therefore it is
necessary to know reverse micelles structure in molecular detail. Molecular dynamics
simulations of reverse micelles are usually performed on pre-assembled micelles as initial
geometry. But experimental information about micellar size and composition is needed to
prepare initial micelle. If this information is unavailable, it is impossible to carry out computing
experiment or its results may depend on the initial conditions.
Recently it is possible to study reverse micelles self-assembly processes in systems that contain
components distributed randomly at start geometry. In this work molecular dynamics simulation
technique was used to explore reverse micelles formation in the three-component system
containing water, hexane, and AOT (sodium bis-2-ethylhexyl-succinosulfonate). Water and AOT
molecules were described at atomic level, but each hexane molecule was reproduced by simple
van der Waalse pseudo-atom. Such different molecules representation increases computational
effectiveness in several times, and allows receive structural information about reverse micelles in
atomic detail.
It has been found typical time scale of molecular dynamics simulation of reverse micelles selfassembly in hexane is at least 50 nanoseconds. And it is viscosity of hexane that defines this
feature. For example, reverse micelles self-assembly processes in solvent supercritical carbon
dioxide require only 5 ns for time scale. In this work it has been investigated influence initial
parameters of systems (such as water and AOT concentrations, and starting component
distribution – in all, 5 different systems) on molecular dynamics simulation results: namely,
reverse micelles structure, their shape, size, components distribution, and surface area per one
AOT molecule. It was revealed that micelles shape tends to sphere in a wide range of AOT and
water concentrations. If micelle shape assume to be ellipsoidal with main semi-axes a, b, and c
(a > b > c) than ratios c/a were found to be between 1 and 0.8 for all micelles. The partial density
of water was found to be approximately 1.0 g/cm3. The surface area on micelle core covered by
one AOT molecule varies in the range of 60 and 80 Å2. All parameters found have no
dependences with initial conditions of modeling, and were found to be in good agreement with
available experiment data. That is why molecular dynamics simulation of reverse micelles selfassembly is a forward-looking technique for investigation of reverse micelles in atomic level
detail.
This work was supported by the Russian Foundation of Basic Research (project no. 07-0300397a) and the Program of Fundamental Research RAS no. 27 “Basic of fundamental research
in nanotechnology and nanomaterials”.
171
SUPRAMOLECULAR ENSEMBES OF Ru(II) PHTHALOCYANINATE,
NONLINEAR OPTICAL AND PHOTOREFRACTIVE PROPERTIES
L.Ya. Pereshivko, A.V. Vannikov, A.D. Grishina,
V.I. Zolotarevsky, Yu.G. Gorbunova, Yu.Yu. Enakieva,
T.V. Krivenko, V.V. Savelyev, A.Yu. Tsivadze
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
van@elchem.ac.ru
Principal direction of our works is the elaboration of the photorefractive (PR) composites based
on polymers having high glass transition temperature Tg. The high Tg polymers improve the
stability of composite characteristics but require the use of the nano-dimensional nonlinear
optical chromophores (NLO). Indeed, the chaotic orientation of any sizes dopants is frozen in the
polymers with high Tg and therefore the possibility of orientation polarization of NLO
chromophores is eliminated, the second order nonlinearity goes to zero but the third-order
susceptibility has a nonzero value: χ(3) = Nγ f4<cos4ξ>. Here N is the concentration of the
chromophores, γ is the third-order molecular polarizability, f = (n0 + 2)/3 is the Lorentz field
factor. The mean value of <cos4ξ> equals 1/5 at a random distribution of orientation angles ξ of
NLO chromophores. The third order susceptibility increases with the increase of the exciton
delocalization length and achieves the highest values for nano-dimensional formations. Nanodimensional chromophores have the long-wavelength optical absorption and were used as
spectral sensitisators to near IR region. The polymer composites consisting of
polyvinylcarbazole (PVK) and ruthenium(II) tetra-15-crown-5-phthalocyaninate with axially
coordinated molecules of triethylenediamine (R4Pc)Ru(TED)2 and ethylisonicotinate
(R4Pc)Ru(EIN)2 as NLO chromophores and also as spectral sensitisators to wave-lengths 1064
nm and 1550 nm, correspondingly, are concerned. Photorefractive polymer layers were cast from
the tetrachloroethane solution of the components. The better results were achieved after 4 cycles
of heating of the Ru(II) complexes solution to 70oC and slow cooling to room temperature. The
two-beam coupling gain coefficient of polymer composite containing (R4Pc)Ru(TED)2 equals Γ
= 140 cm–1 and net gain coefficient Γ– α = 102.3 cm–1 at E0 = 100V/µm and 1064 nm (α is
coefficient of optical absorption). Composites based on (R4Pc)Ru(EIN)2 reach Γ = 48.3 cm–1 or
Γ - α = 42.3 cm–1 at E0 = 100V/µm and 1550 nm. Optical absorption of the fresh
tetrachloroethane solutions of complexes have maximum at 626 - 627 nm and longwave
boundary near 900 - 1000 nm but spreads out to 1400 nm for (R4Pc)Ru(TED)2 and to 1650 nm
for (R4Pc)Ru(EIN)2 in result of 4 cycles of heating to 70oC/slow cooling of the solutions. It was
supposed that this spreading arises from the formation of supramolecular ensembles of the
complexes. To argue this suggestion, the images of supra molecular ensemblies of the
(R4Pc)Ru(TED)2 has been obtained with method of atomic force microscopy. The image of the
fresh sample contained cylindrical particles from 50 to 100 nm in diameter and the mean height
of the cylinders was about 2-3 nm. Shown in left Figure the image of the
sample fabricated after heating demonstrates stable supramolecular wires of
7-8 nm in height, 100 (1) – 150 (2) nm in width and 600 nm (3) or more in
length.The positive sign of the third order susceptibility were measured in
the solutions of (R4Pc)Ru(TED)2 complexes with z-scan method. The
molecular polarizability of the complexes is about γ = 4.5×10–32 esu. The
polarizability attributed to one molecule increases by factor of 3.6 when the
individual molecule transfers into a supramolecular ensemble.
This work was supported by the ISTC (Grant No. 3718) and RFBR (projects No. 07-03-13547,
08-03-00125 and 08-03-00835).
172
POLARISATION ANISOTROPY OF SINGLE-CRYSTAL OPAL FILMS
A.I. Plekhanov, V.P. Chubakov, P.A. Chubakov
Institute of Automation and Electrometry SB RAS, Novosibirsk, Russia
fractal@iae.nsk.su
In this reports we have studied the polarization anisotropy of photonic crystal (PhC) [1] opal
films. These films were prepared from monodisperse spherical silica particles (MSSPs).
Diameter of MSSPs was approximately 250 nm. PhCs were obtained by two methods: the
moving-meniscus method (MMM) [2, 3] and gravitational sedimentation method (GSM) [4]. In
the MMM layers of PhC are formed on inclined substrate along projection (on a substrate) of
gravitational force. It produces dedicated direction in PhCs along the line of crystalline growth.
The GSM is used for lyophilic suspensions. A layer of lyophilic suspension of MSSPs spread
over horizontal substrate evenly where opal structure is forming and drying. Similar films do not
have dedicated direction. There are only local irregularities.
We have used films with thickness from 1 to 10 µm. Electron microscopy shows that in both
methods the single-crystalline films are packed from hexagonal layers of MSSPs. These layers
are parallel to substrate and correspond to the crystalline plane [111] of face-centered cubic
lattice (FCC).
It is known that cubic crystalline systems have the same refractive index in all directions, i.e. the
optical indicatrix of FCC have a spherical shape. But our measurements of transmission
spectrum in crossed polarizers show that the samples obtained by both methods (MMM and
GSM) have (surprisingly) polarization axes. These axes have relation to dedicated directions of
PhC films. The films grown by MMM have polarization axis along the line of crystalline growth.
The direction of polarization axis for the films grown by GSM depends on the place of
measuring because surface tensions have influence on the film forming in GSM. It produces
radial irregularities and the local polarization axes are directed along ones.
In addition, ellipsometric measurements show that PhC films have birefringence in the plane of
the substrate. If these films were filled by some immersion liquid with equal refractive index to
silica, birefringence disappears. The difference between the highest and lowest refractive index
for the samples prepared by MMM is ∆n ~ 2·10-3. Conoscopy measurements show the following:
the indicatrix of refractive index for MMM films is three axial ellipsoid with the angle 2V equals
to 17º between optical axes. The axis of indicatrix Ng directs along the line of crystalline growth,
Nm lays in the plane of the surface of film and is orthogonal to Ng. The axis Np coincides with
normal to the crystalline plane [111]. The axis Np is a bisector of the angle 2V. It shows that the
films prepared by MMM are optically negative crystals. The measured differences of refractive
index in the plane of indicatrix axes are ng – nm ~ 2·10-3, ng – np ~ 8·10-2. It is a high
birefringence and the orientation of indicatrix axes relative to crystallographic axes corresponds
to triclinic system.
For the first time a high birefringence was found in the PhC films obtained by MMM and GSM.
This phenomenon demands an adequate theoretical description and takes into account at the
engineering of the elements for photonics.
This study was supported by the integration project of the SB RAS №17 and by the Program № 8
of Physical Sciences Division of the RAS.
1.
2.
3.
4.
K.Sakoda ,“Optical Properties of Photonic Crystals”, Springer-Verlag Heidelberg 2005.
Y.V. Vlasov, X. Zh. Bo, J. C. Sturm, D. J. Norris, “Nature, 2001. V. 414. No. 15. P. 289.
A.I. Plekhanov, D.V. Kalinin, V.V. Serdobintseva, Russian nanotechnol., 2006, №1, P.245.
D.V. Kalinin, V.V. Serdobintseva, V.F. Shabanov, Doklady Physics, 2008. V. 53. № 4. P.192.
173
LASING IN PHOTONIC CRYSTAL OPAL FILMS
AND HETEROSTRUCTURES
A.I. Plekhanov, A.S. Kuchyanov
Institute of Automation and Electrometry SB RAS, Novosibirsk, Russia
fractal@iae.nsk.su
One of the applied aspects of photonic crystals (PhC) is connected with the creation of effective
light-emitting diodes and tiny laser sources. The effective light source is based on threedimensional PhC with photonic band gap (PBG) and an active material with the emitting band
which is coincident with the PBG. A potentially simpler and cheaper approach for creating threedimensional periodic structures is the natural assembly of colloidal microspheres. One of such
nanoscale regular structure is artificial opal. The opal structure opens wide prospects for
composites with liquid crystals, laser dyes, etc. But artificial volume opals have usually irregular,
polycrystalline structure. The single-crystalline PhCs that have defect densities sufficiently low
then the artificial opals can obtain by assembling a thin layer of colloidal spheres on a glass
substrate. To date, the lasing in artificial volume opal and in single-crystal opal film were
observed [1,2].
We have studied the lasing in volume artificial opal, single-crystal opal films and opal
heterostructures doped with Rhodamine 6G and excited by picosecond pulses of a second
harmonic from a Nd:YAG laser. The artificial opals were prepared from crystallizing colloidal
suspension of highly monodispersed spherical silica particles (MSSP) with the diameter ranging
from 190 to 250 nm. The single-crystal opal films were prepared from a suspension of MSSP in
a dynamic meniscus area [3].
The lasing threshold for Rhodamine 6G in the volume opal was found to be equal to
13 MW/cm2. The random lasing in artificial opals always peaks at the maximum of dye
luminescence band. The generated peak is independent of the PBG.
We have shown that monochromatic and directed laser emission can be obtained from dyeinfiltrated single-crystal opal films. This lasing caused by Bragg diffraction inside of PhC, i.e.
associated with the periodicity structure of the opal film. In this case the lasing always peaks at
the boundary of the PBG. The excitation intensity threshold was about 2.5 MW/cm2. We have
obtained also the lasing in three-layered heterostructure. It was found the outer PhC layers of this
heterostructure serve as two-mirror cavity. This reduced the threshold by 3 times as compared
with one-layer single-crystal film.
This study was supported by the integration project of the SB of the RAS No.17 and by the
Division of Physical Sciences, the RAS (program No. 8).
1. Frolov S.V., Vardeny Z.V., Zakhidov A.A., Baughman R.H. // Opt. Communs., 1999, v.162,
p.241.
2. Nishijima Y., Ueno K., Juodkazis S., Mizeikis V., et.al. // Optics Express, 2008, V. 16, No.
18, p.13676.
3. Plekhanov A.I., Kalinin D.V., Serdobinsteva V.V. // Nanotechnologies in Russia, 2006, v.1,
No.1,2, p. 245.
174
POLARIZATION AND ORIENTATION ANISOTROPY OF RESONANT
OPTICAL PROPERTIES IN POLYMER 3D PHOTONIC CRYSTALS
A.V. Selkin1, V.G. Fedotov1, T.A. Ukleev1,
A.Yu. Menshikova2, N.N. Shevchenko2
1 – A.F. Ioffe Physical-Technical Institute RAS, St.Petersburg, Russia
2 - Institute of Macromolecular Compounds RAS, St.Petersburg, Russia
alexander.selkin@mail.ioffe.ru
Interaction of electromagnetic field with spatially-periodic solid-state structures which
permittivity changes with spacing comparable with wavelength of light is accompanied by a
number of striking diffractive optical phenomena that can be assigned to strong modification of
the eigenmode energy spectrum. These structures, the called photonic crystals (PhC), have been
attracting intense interest that can be traced to the possibility of efficient control of light
propagation within PhC and to currently emerging applications in laser technology and
optoelectronics. On the other hand, such structures are novel nontrivial objects that can be used
to advantage in exploring fundamental aspects of nanophotonics.
We report here on experimental and theoretical studies of the mechanisms accounting for the
spectra of resonant Bragg diffraction from polymer PhCs with the opal fcc crystal lattice. We
used for model experimental objects the polymer PhC films made up of monodisperse
polystyrene particles. Attention is focused primarily on an investigation of novel optical effects
associated with polarization and orientation anisotropy of PhC possessing high dielectric
contrast. Such kind of anisotropy is shown to be a specific property of three-dimensional (3D)
PhC, which looks unusually in terms of traditional crystal optics. A special feature in interaction
of light with 3D PhC is due to the following factors: (i) the fulfillment of the condition when
resonant Bragg diffraction occurs simultaneously on the crystal planes non-parallel to each other,
(ii) the specific spectrum of electromagnetic PhC eigenmodes with an account of surfaces and
interfaces and (iii) the polarization properties of the eigenmodes for which, in general, fails usual
TE-TM classification with respect to the polarization state.
An analysis of experimental data was carried out within the framework of the approach [1]
suggested earlier. A good agreement between the results of theory and experiment is
demonstrated thus being evidence in favour of the generalized Ewald-Oseen extinction principle
as applied to the 3D PhC structures whose spatial period is comparable with the wavelength of
light [2]. We call attention here to the existence of the regions in the energy spectrum of PhC
where more then one eigenmode can be excited at the same frequency. This kind of multimode
regime of light propagation inside the PhC means that additional boundary conditions for the
field amplitudes are required as it is done for instance in crystal optics with spatial dispersion of
dielectric function [3].
1. A.G. Bazhenova, A.V. Sel’kin, A.Yu. Men’shikova, and N.N. Shevchenko. Physics of the
Solid State, 49, No.11, pp. 2109-2120 (2007).
2. P.A. Belov, C.R. Simovski. Phys. Rev. B 73, 045102 (2006).
3. V. Agranovich and V. Ginzburg. Spatial Dispersion in Crystal Optics and the Theory of
Excitons (Wiley-Interscience. New York, 1966).
175
NANOPHOTONICS OF FULLERENE SOLUTIONS
E.F. Sheka1, B.S. Razbirin2
1 - Peoples’ Friendship University of Russia, Moscow, Russia
2 - A.F. Ioffe Physical-Technical Institute RAS, St.Petersburg, Russia
b.razbirin@mail.ioffe.ru
Nanophotonics of fullerenes is mainly associated with the impact of low doping of fullerenes on
characteristics of nonlinear optical (NLO) media and, as a result, of NLO devices. Obvious
electromagnetic nature of NLO effects enhancement and a direct influence of electric field on the
enhancement witness convincingly the recruitment of charge states in the considered features.
These states have been explained by the formation of charge transfer complexes due to donoracceptor (DA) interaction between fullerenes and host matrices. The paper concerns the origin,
structure, and spatial extension of the complexes. Empirically, the complexes are studied via
enhancement effects which follow Raman scattering and one-photon luminescence of fullerenedoped matrices. Computationally, the DA interaction is considered through its influence on the
total intermolecular interaction between solute (fullerene) molecules (sol-sol interaction) as well
as between solute and solvent molecules (sol-solv interaction).
Empirical features are exhibited by an additional blue emission spectrum in diluted fullerenedoped matrices which appears under excitation in the visible and near UV regions subjected to
resonance conditions [1-3]. The blue spectrum presents a combination of enhanced Raman
scattering and enhanced one-photon luminescence of both solvent and fullerene molecules, the
latter involved in clusters, and is attributed to the enhancement of linear optical effects caused by
the formation of sol-sol and sol-solv clusters. A particular contribution of these spectral
components into the blue emission of a certain solution depends on chemical structure of the
fullerene. Quantum-chemical computations performed in the study permitted to evaluate the
strength of the intermolecular interaction in the clusters and highlight their charge-transfer
origin.
The observed enhancement of linear optical events is considered within the framework of the
enhancement local field model and is connected with the resonance excitation of the clusters
which are spatially extended charge-transfer complexes. The excitation light is transformed into
local charge-transfer excitons within the clusters providing the polarization of the medium
enough for the enhancement of the local electric field of the incident and outgoing light. A direct
connection is established of the intensity of the observed linear optical features with the efficacy
of the media nonlinear behavior, at one hand, and with a coupling strength of the cluster
formation, on the other. Empirical and computational probing is suggested that permits to test a
fullerene-doped matrix for its applicability towards nonlinear optical applications.
The work is financially supported by the RFBR (grant № 07-03-00755).
References
1. B.S. Razbirin, E.F. Sheka, A.N. Starukhin, D.K. Nelson, P.A. Troshin, R.N. Lyubovskaya,
JETP Lett. 87, 133 (2008)
2. E.F. Sheka, B.S. Razbirin, A.N. Starukhin, D.K. Nelson, M.Yu. Degunov, L.N. Lyubovskaya,
P.A. Troshin, JETP. 108, 738 (2009) [ZhETF 135, 848 (2009)].
3. E.F. Sheka, B.S. Razbirin, A.N. Starukhin, D.K. Nelson, M.Yu. Degunov, P.A. Troshin, R.N.
Lyubovskaya J.Nanophot. SPIE 3, 033501 (2009)
176
NANOPHOTONICS IN PRINTING AND PACKAGING.
DIGITAL AND ANALOGUES IMAGES TREATMENT AND PRODUCING
V. Sherstiuk, S. Molodid
National Technical University of Ukraine “Kiev Polytechnic Institute”
sherstyukv@ukr.net
The achievements and perspectives of nanosciences and nanotechnology determine the modern
stage of scientific and technical progress. The trends are considered in microminiaturization in
printing and some features of dispersed systems in nano sized scale as well as their applications
in Graphic Arts and packaging.
The trend toward ever-smaller semiconductors was first noticed as long ago as 1965 according
the formulation now known as Moore's Law: The number of components that can fit on an
integrated circuit (and quantity of information, correspondently) doubles every 18 months to two
years. On the Moore’s diagram at beginning of 1980-es the minimum dimension of elements of
electronic devices to the period of 2005-2010 must be less 0.1 µm or 100 nm. It means that
elements in electronic and photonic devices must have sizes of nanometer dimension. The
imprint lithography is now one of the perspective ways for producing micro- and nanosized
devices. But there are problems of preparing photo masks by means of usual photography. That
is why it is reasonable to look at the lithography and photolithography development and the
problem of the images treatment in analogous and digital versions. There were compared images
formation and transformation from digital to analogous and there and back. The modern
imprinting lithography as a kind of nanotechnology is concerned in view of future security
printing, producing RFID tags and other applications for packaging.
Now there are actual synthesis and stabilization of nanoparticles and photoactive
nanocomposites in polymer matrixes and on the surfaces for their utilization by micro- and
nanocontact printing techniques. Dimensions of nanoparticles grow spontaneously usually. The
problem of obtaining particles of certain size and geometry is rather important and actual. The
nanocomposites stabilized will be perspective in different areas of printing nanotechnologies.
Luminescent compositions may be rather attractive for printing and packaging. Improving of
light emission (in photo, electric and magnetic fields) of dispersed compositions and filled
polymer composites and nanocomposites is dealt with understanding of the influence of size of
particles, value of surface, formation of electron acceptor and electron donor centers on the
surface.
The aggregation of dispersed particles during transformation of ink-varnish nanocompositions
into fixed prints changes the luminescence parameters. Properties of photo emitting
nanocomposites depend upon the nature and parameters of surroundings. Thus, the fundamental
tasks for investigation of influence of these factors upon the efficiency of luminescence and
stabilization of the nanocomposites properties are to be considered and studied. Special ink
systems were designed for the identification of authenticity of printed matter by the luminescent
and magnetic properties of inked impressions. There was discovered that paramagnetic
properties of magnetite particles with luminofor molecules changed at UV light illumination. It
was found that the introduction of luminescent substances into general-purpose printing inks
causes luminescence quenching by printing-ink curing catalysts. Magnetite particles coated with
luminescent substances exhibit changes in the magnetic (in particular, paramagnetic) properties
depending on the luminescent molecules nature and the surface pre-treatment procedure
The study was carried out at the financial support of the State Foundation of Fundamental
Researches, Ministry of Education and Science of Ukraine (the project No.F25.4/052).
177
PHOTOPHYSICAL AND PHOTOCHEMICAL EFFECTS IN
ASSEMBLIES OF NANOPARTICLES IMMOBILIZED ON METAL
OR DIELECTRIC SUBSTRATES AND MOLECULAR TEMPLATES
N.D. Strekal, S.A. Maskevich
Yanka Kupala Grodno State University, Grodno, Belarus
nat@grsu.by
Semiconductor nanoparticles with CdSe emissive core and passivative ZnS shell (CdSe/ZnS
NPs) are well known fluorophores with a number of advantages over organic fluorophores. The
electronic spectra of NPs are size-dependent due to quantum confinement effects and the term
Quantum dots (QDs) is widely used for designation them in the line of other systems of low
dimensionality. They posses of a wide (from UV to red range in dependence of its size)
absorption band, narrow (ca 30 nm) photoluminescent (PL) band and narrow (ca 5 nm) Stocks
shift between the long-wave edge of absorption and PL bands. The overlapping of NPs excitation
profiles enable NPs with different emission wavelengths to be simultaneously excited. That
advantage is very important in multiplex application1. The use of broadband excitation source
posses also the extremely high brightness and photostability. The nanocrystalline nature of these
objects display superior chemical (dispersible in different solvents), photochemical and
photophysical properties. There are many applications that have been proposed for CdSe/ZnS
NPs: optoelectronics, tunable lasers and LEDs, photonics, biosencing and bioimaging etc.
The aim of our work is the engineering of self-assembled NP superlattices of different level (1D
or 2D) with presumably collective properties. With this aim we use the different capping agents
to redisperse the NPs in aqueous solution and self-assembled immobilization on the plane
dielectric, plasmonic gold surface or molecular templates.
We have obtained self-aggregated patterns of CdSe/ZnS NPs (3,2 nm in diameter, Birch Yellow,
www.evidenttech.com) on different substrates. On the surface of chemically modified glass
(Silan prep, Sigma) these patterns present the rings and globules of different sizes and shapes. It
was revealed that big (in comparison to light wavelength) and initially bright aggregates develop
the bleaching with time under continuous illumination. The same illumination causes the
increase of PL intensity for little NP globules and rings up to two orders of magnitude. Emission
from the samples with photoactivated properties becames polarized when PL signal reached the
saturation. The degree of polarization grows up to 20-30% if excitation laser light has s –
poliarization. Also mean PL decay time strongly decreases as result of photoactivation from tens
of nanoseconds (for NPs in aqueous solution) to picosecond range for NP photoactivated
aggregates on glass slides. PL properties of these QDs ensembles strongly depend on excitation
conditions. The set of observed data shows that the PL enhancement may not be only
accompanied by QD surface rearrangement and photooxidation (chemical effects of light) but
also may be caused by some optical alignment of QD excitons by plane-polarized light (electromagnetic effects). Some alignment of excitons is recently presented in 2.
The bright and stable fluorescent nanowires were obtained by molecular combing of cationic
polyelectrolites (PE) complexes with mercaptoacetic acid capped CdSe/ZnS NPs (anionic NPs).
It was determined that NPs size as well as PE:NPs stoichiometric molar ratio are the crucial
parameters, which define the topology of NPsPE complexes stretched on solid substrate. The
conditions for formation nanowire complexes based on NP-labeled PAA also were found.
The spectral overlap of plasmon excitation band and NP emission band as key factors
influencing on PL enhancement under immobilization on gold plasmonic films is also discussed.
1
R. L Ornberg, T. F. Harper, H. Liu. // Nature Methods 2, 79 - 81 (2005).
Gaponenko S.V. at al. Optics of nanostructures. (Russ) Ed. by Fedorov A.V. St-Petersburg, Russia. Nedra, 2005,
326 p.
2
178
SEMICONDUCTOR PHOTOCATALYSIS ON THE NANOSCALE:
STATE-OF-THE-ART AND PERSPECTIVES
A.L. Stroyuk, S.Ya. Kuchmiy, A.I. Kryukov, V.D. Pokhodenko
L.V. Pysarzhevsky Institute of Physical Chemistry NAS, Kyiv, Ukraine
stroyuk@inphyschem-nas.kiev.ua
A background and principles of semiconductor nanophotocatalysis – a new trend in
photochemistry dealing with the photocatalytic redox-reactions with the participation of
semiconductor nanoparticles – is discussed. The origins of various size-dependent phenomena in
the semiconductor photocatalysis are highlighted with the special attention paid to the quantum
size effects originating from a spatial confinement of the photogenerated charge carriers
(excitons) in ultra-small semiconductor nanoparticles (quantum dots). The specifics of quantumconfined semiconductor nanoparticles is discussed, including the size-dependent optical
properties (the position and shape of absorption and photoluminescence bands, the oscillator
strength of interband electron transitions, etc.), thermodynamic characteristics (the band gap, the
potentials of conduction and valence band edges, the nature, number and depth of charge
trapping sites, etc.), as well as the dynamics of photogenerated charge carriers (charge migration
in semiconductor nanoparticles, its localization on the structure defects, interfacial charge
transfer, etc.).
The most important consequences of spatial exciton confinement in semiconductor nanoparticles
affecting their photocatalytic behavior are discussed. Particular attention is paid to the
development of the photocatalytic properties in narrow-band-gap semiconductors at the
nanoscale, the increase of a number of photocatalytic reactions for a given nanocrystalline
semiconductor as compared with the bulk material, and the acceleration of photocatalytic
reactions with the participation of semiconductor nanoparticles due to size-dependent growth of
the energy of charge carriers. The photoinduced polarization caused by the accumulation of
excessive charge by semiconductor nanoparticles and resulting in a remarkable increase of their
photocatalytic activity is discussed.
The specific features of the photocatalytic behavior of semiconductor nanoparticles are
illustrated in the chapter by a number of examples. In particular, the size-related phenomena in
the photocatalytic metal reduction, photocatalytic formation of binary semiconductor
nanoheterostructures, photoinduced polymerization of acrylic monomers, photocatalytic
reduction of sulfur compounds, and photocatalytic water reduction with the participation of
semiconductor nanoparticles are discussed. Special attention is paid to the photochemical
behavior of quantum-confined semiconductor nanoparticles under powerful pulse illumination.
The examples of simultaneous and additive influence of different size effects upon the
photocatalytic properties of semiconductor nanoparticles are demonstrated.
In conclusion, perspectives of future development of the photocatalytic systems based on
nanostructured semiconductors are given, outlining the ways for their further perfection,
broadening of the number of known nanophotocatalysts and photocatalytic processes, as well as
the benefits of the utilization of such systems in modern nanotechnologies.
179
COFLUORESCENCE OF DYES IN NANOSTRUCTURES
OF METAL ION COMPLEXES WITH DIKETONES
E.B. Sveshnikova, V.L. Ermolaev, S.S. Dudar
St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
ermolaev@oi.ifmo.ru
The phenomenon of Ln3+ luminescence enhancement in structures of their complexes was given
the title of columinescence. Beginning from nineties of last century this phenomenon has a wide
use in chemical and immuno-luminescent analysis. We have shown for the first time that
columinescence intensity of Ln3+ complex nanostructures (NS) in aqueous solutions is
determined not only by migration of ligand triplet energy of complexes forming NS, to
complexes of Eu3+, Tb3+ or other luminescent ions; but also by the increase of luminescence
yield of these complexes under their incorporation into NS.
It is found by us that the sensitized fluorescence (cofluorescence) of dye molecules occurs under
their incorporation in NS of diketonate complexes of metal ions in aqueous solutions. We
revealed [1] that in aqueous solutions of β-diketones (0.1–30 µm), Eu3+, Gd3+, Al3+, Sc3+, In3+
(0.1–30 µm) and dye molecules (1–1000 nm) NS of ion complexes with dye admixture are
formed. Irradiation of such NS into the ligand absorption band leads to dye cofluorescence
appearance if the excited singlet levels of dyes are situated below than the analogous ones of
diketone. The cofluorescence intensity is shown to depend on NS size and morphology, choice
of ions of complexes, forming NS and quantum yield of dye fluorescence in NS. Dye
cofluorescence is examined in NS of four diketonate and hydroxy-diketonate complexes of ions
with cationic forms of dyes: nile blue, malachite green, rhodamine 6G and B, cryptocyanine and
other ones.
There are two processes of dye sensitization in NS of Eu complexes with admixture of dyes
having S1 level below than 5D0 level of Eu3+: S–S energy transfer from ligands to dyes which
leads to dye cofluorescence with ns lifetimes, and energy transfer from Eu3+ to dye that is
responsible for delayed dye cofluorescence with 1–50 µs times. It is shown that at dye
concentration in solution less than 100 nM the delayed cofluorescence dominates in the
integrated sensitized dye fluorescence. At higher dye concentrations the intensity of usual and
delayed cofluorescence are commensurable and concentration quenching of dye fluorescence is
observed. S–S energy transfer to dyes is observed even in those NS where complex fluorescence
is not detected. The discovery of dye cofluorescence in NS allows to expand a set of different
spectral luminescent labels in analyses, including time-resolved immuno-analysis and allows
also to enhance the sensitivity of luminescence method of analysis, using dye molecules as
labels.
1. Dudar S.S., Sveshnikova E.B., Ermolaev V.L. Optics and Spectroscopy, 2008, V.104, No 2,
pp. 225–234; No 5, pp. 724–731; 2009, V.107, No 1 (in press).
180
NANOSIZE STRUCTURES IN POLYMER BASED SOLAR CELLS
A.R. Tameev, A.V. Vannikov
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
tameev@elchem.ac.ru
Nanosize structures (nanoclusters, NCs, and nanoparticles, NPs) of organic and inorganic
materials are of interest for studies of photo-physics and applications in organic solar cells.
Among polymer materials, bulk heterojunction solar cells based on polyphenylenevinylene
derivatives (MEH-PPV, MDMO-PPV) or polythiophene derivative (P3HT) and fullerene
derivative (PCBM) yield the most power conversion efficiency (~ 5%) [1-3].
The nanosize structures are formed in a polymer composite even in the course of thin layer
casting from solution. We have demonstrated the formation of ordered molecules NCs in thin
layers of MEH-PPV and NCs influence on charge carrier transport behaviors and mobility and
photovoltaic characteristics [4,5]. PCBM molecules (electron acceptors as well as quenchers of
polymer luminescence), form NCs in the process of preparation of the polymer composition. The
PCBM NCs define the morphology of the polymer layers and therefore photovoltaic parameters
of the cells [6].
Nanosize crystals of J-aggregated cyanine dyes embedded in a polymer composition provide
reasonable high mobility of charge carriers [7] resulting in increased photovoltaic current in solar
cell [8]. The charge transport behaviors in polymer composites doped with the cyanine dye Jaggregates and single-walled carbon nanotubes (SWNTs) are similar [7,9]. SWNTs are also used
in the development of organic solar cells.
Photophysical properties of metal NCs and NPs are of particular interest for utilization in organic
solar cells [10]. Au and Ag NCs (NPs) introduced between an electrode and photoactive polymer
layer were found to increase photovoltaic current a several times [11]. The enhancement of the
photovoltage is due to incident light which excites a surface plasmon on the metal NP. In this
process, the NP (NC) can then (1) re-radiate most of its energy into the polymer in such a way
that the light is trapped inside the cell, (2) transfer its energy to a single electron within the metal
NP, emitting the electron [12]. The interaction between light and metal NPs also leads to
increases in the electromagnetic field around the particles. This will increase the light absorbed
by the organic (polymer) molecules in that region and consequently the number of charge
carriers [10].
In the report, experimental results and discussion of the mentioned above problems are
presented.
The work was supported by the RFBR (08-03-00796, 07-03-00149) and ISTC (3718) projects.
References
1. H. Hoppe and N.S. Sariciftci, J.Mater. Chem. 16 (2006) 45.
2. B.C. Thompson and J.M.J. Frechet, Angew. Chem. Int. Ed. 47 (2008) 58.
3. P.A. Troshin, R.N. Lyubovskaya, V.F. Razumov, Nanotechnol. in Russia. 3(5-6) (2008) 242.
4. A. R. Tameev, S. V. Novikov, A.V. Vannikov et al., Proc. IEEE 4th World Conf. Photovoltaic Energy
Conversion, 2006. V.1. P.244–246.
5. Y-F Huang, A.R. Inigo, C-C Chang et al., Adv. Funct. Mater. 17 (2007) 2902.
6. D. Chirvase, J. Parisi, J.C. Hummelen and V Dyakonov, Nanotechnology 15 (2004) 1317.
7. A. R. Tameev, S. V. Novikov, A.V. Vannikov. Ross. Nanotechnol. 2(11-12) (2007) 97 (in Rus).
8. A.R. Tameev, A.V. Vannikov, and H.F.M. Schoo, Thin Solid Films 451-452 (2004) 109.
9. A.R. Tameev, L.Ya. Pereshivko, A.V. Vannikov. Mol. Cryst. Liq. Cryst. 497 (2008) 333.
10. B.P. Rand, P. Peumans, S.R. Forrest, J. Appl. Phys. 96 (2004) 7519.
11. V.A. Kolesnikov, A.R. Tameev, S.V. Novikov et al. Proc. 19th Eur. Photovoltaic Solar Energy Conf., 2004.
P.363-366.
12. M.Westphalen, U. Kreibig, J. Rostalski et al., Sol. Energy Sol. Cells 61 (2000) 97.
181
SPATIAL DISPERSION AND LOCAL FIELD EFFECTS FOR
SEMI-INFINITE MEDIA WITH EMBEDDED NANOPARTICLES
A.A. Tishchenko, M.I. Ryazanov, M.N. Strikhanov
MEPhI, Moscow, Russia
tishchenko@mephi.ru
The well known fact is that the average field acting on a molecule differs from the macroscopic
field. The usual way is to call the field obtained by averaging the solution to the microscopic
Maxwell equations over the quantum states of atomic electrons and the thermal motion of nuclei
– to call it by macroscopic field [1], and to call average field acting on a single molecule by local
field. The effects resulting from the difference between the local and macroscopic fields are
called local field effects. Relations between the external field, the macroscopic field and the local
field lead to the Clausius–Mossotti formula; for three-dimensional systems this can be obtained
by using a pair distribution function for molecules [2].
In this paper the Clausius-Mossotti relation have been obtained for half-infinite medium with the
monolayer of other particles on its surface. The interaction between a molecule and an
electromagnetic field is analyzed in the dipole approximation, which is good approximation at
wavelengths much longer than the intermolecular distance. For the three limits the results
couincide with ones obtained before: i) the case of infinite medium give us the standard, wellknown Clausius-Mossotti relation [3]; ii) the case of half-infinite medium without surface
monolayer. Here Clausius-Mossotti relation is obtained with corrections due to limitation in one
direction. The divergence is considerable near the surface and vanishes far from it [4]; iii) the
case of a monolayer only, without the substrate - this limit gives the expressions obtained in Ref.
[5]. It should be mentioned that in this work the relations between the local and macroscopic
field are only treating; to find a relation between the local field and a field of external sources in
3D case is more difficult problem, and it is not dealt with here. The effects of spatial dispersions
are considered. Also, the possible applications of the theory developed are discussed.
References
1. V.L. Ginzburg, Application of Electrodynamics in Theoretical Physics and Astrophysics.
(Gordon and Breach, 1989).
2. O.V. Dolgov and E. G. Maksimov, Usp. Fiz. Nauk 135 (1981) 441.
3. M.I. Ryazanov, Electrodynamics of Condensed Matter (Nauka, Moscow, 1984) [in
Russian].
4. M.I. Ryazanov, JETP 83 (1996) 529 [ZhETF 110 (1996) 959].
5. M.I. Ryazanov and A.A. Tishchenko, JETP 103 (2006) 539 [ZhETF 130 (2006) 621].
182
ORDERED STRUCTURES ON THE BASIS
OF SELF-ASSEMBLY OF CdSe AND Au PARTICLES
M.A. Zaporohzets1, V.I. Nikolaichik2, V.V. Volkov1,
D.A. Baranov3, К.А. Dembo1, S.N. Syl’yanov1, O.M. Zhigalina1,
S.P. Gubin3, A.S. Avilov1, I.I. Khodos2
1 – A.V. Shubnikov Institute of Crystallography RAS, Moscow, Russia
2 - Institute of Problems of Microelectronics Technology RAS, Chernogolovka, Russia
3 - N.S. Kurnakov Institute of Gen & Inorg Chemistry RAS, Moscow, Russia
zaporozhets_m.a@mail.ru
Preparation of monodisperse nanoparticles of different materials is one of the important current
problems of nanotechnology development. Apart from the fact that nanoparticles themselves
have the unique set of physical properties, size uniformity of nanoparticles provides a potential
possibility to form diverse structures from them. An effective mechanism of structure formation
is self-assembly of particles into so called “superlattices”, where similar to atoms in classical
crystals, nanoparticles are ordered in a strictly definite manner. In order for that to be realized,
development of effective methods of nanoparticles synthesis providing a narrow size distribution
and maximum form similarity is needed. It is expected that ordered structures made of
nanoparticles will display new properties different from the properties of isolated nanoparticles.
Preparation techniques of two types of nanoparticles - cadmium selenide and gold - have been
developed, and ordered structures on their basis have been prepared in this study. CdSe
nanoparticles were synthesized by interaction of cadmium stearate with triphenylphosphine in
heptadecan mediumin at the presence of oleamin and triphenylphosphine oxide as surface active
agents (SAA). Au nanoparticles were prepared by reduction of HAuCl4 in hexane through boron
hydride at the presence of SAA.
The analysis of X-ray and electron diffraction patterns have revealed that samples of CdSe and
Au nanoparticles are single phased. CdSe nanoparticles have a wurzite structure (the P63mc
space group). Crystal structure of Au nanoparticles is described in terms of face centered cubic
lattice (the Fm3m space group). It is found by techniques of high resolution electron microscopy
and X-ray small angle scattering that prepared samples contained nanoparticles of spherical form
with a narrow size distribution. An average size of CdSe nanoparticles was 12 nm, and that of
Au nanoparticles was 10 nm. Nanoparticles form observed in a transmission electron microscope
did not change at sample tilting that supports its spherical character.
Self- assembly of nanoparticles into close-packed 2D ensembles having the 6-order symmetry
axis was observed in regions with high deposition density of CdSe nanoparticles onto carbon
substrate. The pronounced texture was present in CdSe ensembles such that all nanoparticles
were orientated with the [001] direction perpendicular to carbon film surface deposited with
nanoparticles. A new type of ordered CdSe ensembles formed of particles with fine-domain
structure has been found.
No texture in the form of either preferred orientation of nanoparticles crystal structure in relation
to each other or to the substrate has been found in 2D close packed ensembles of Au
nanoparticles. The 3D structures of Au nanoparticles have been found where the second layer of
nanoparticles resides in voids of the first layer forming a close-packed bulk ordering of
nanoparticles in that manner.
183
OPTICAL PROPERTIES OF NANO-STRUCTURED
POLYMER LIQUID CRYSTAL COMPOSITES
G.M. Zharkova, A.P. Petrov, V.M. Khachaturyan
S.A. Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia
Zharkova@itam.nsc.ru
Now the production of new high-structured functional materials on the base of polymer-liquid
crystals composites is studied intensively. The holographic method, based on the photopolymerizing composition emitted with the light of an interferential pattern, permits to form the
composites with the periodic structural formations of nano-size range [1].The presence of the
developed surface of the supramolecular structures of such composites, on which boundary the
initial orientation of the liquid crystal (LC) forms, as well as this surface periodicity change the
optical properties of the composite. The formed composites show diffraction properties, and their
optical properties can be tunable.
The influence of the supramolecular formations geometry of the polymer liquid crystal
composite on the orientation distribution of molecules in a small volume has been analyzed
theoretically. It has been revealed that the LC molecule orientation is affected by the orienting
effect of the volume geometry and the ratio of the liquid crystal elasticity factors (splay and
bend) К1/К3.
Under analysis are the evolution of the NLC optical properties regarding the type and
characteristic sizes of the supramolecular structure of the composites formed by the
photopolymerization method. The composites formed at the pre-polymer light exposition with
the uniform and non-uniform intensity distribution (the holographic method) have been studied
experimentally. In the first case, polymer-disperse liquid crystals are formed (a). In the second
case, this is a structure consisting of alternating bands enriched either with the polymer or with
the LC (b) [2].
a)
b)
The optical properties of the composites have been compared subject to the formed structure; the
peculiarities of the light diffraction on the photopolymer liquid-crystal composites, caused by the
nano-size structural formations, have been analyzed.
1. Sutherland R.L., Natarajan L.V., Tondiglia V.P., Bunning T.J. Bragg gratings in an acrylate
polymer consisting of periodic polymer-dispersed liquid-crystal planes // Chem. Mater. 1993.
V. 5. pp. 1533-1538.
2. Zharkova G.M, Petrov A.P, Samsonova I.V.and Khachaturyan I.V. Investigation of the optical
properties of polymer-liquid crystal holographic materials for use in photonics// High Energy
Chemistry.2008.Т.42. №7.pp.546-547.
184
POSTERS
DIFFERENTIAL PARAMETERS OF ORGANIC PHOTOELEMENT
WITH BULK HETEROJUNCTION
S.D. Babenko1, Yu.L. Moskvin1, P.A. Troshin2, A.A. Balakai1
1 - Branch of Institute of Energy Problems of Chemical Physics RAS, Chernogolovka, Russia
2 - Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
balakai@binep.ac.ru
Organic bulk-heterojunction solar cells have attracted considerable attention as a promising
approach to future photovoltaic energy sources. Improvements in performance are depend on
developing a better understanding of the pertinent processes such as charge separation, geminate
recombination, shunts, and leakage.
The pulse laser method of probing has been employed to determine differential parameters of
such cell. The values have been estimated from the transient photopotential with different
loading resistances. Serial and shunt internal resistances, capacity, and relative charge separation
efficiency have been measured over voltage range (-1400 mV ÷ 600 mV).
The received values of resistances and separation efficiency show an agreement with once
deduced from J-V characteristics in dark and under pulse illumination. It has been revealed 6fold growth of measured capacity at direct applied voltage (fig.1.)
Fig.1. Differential capacity (Cdif) as a function of applied voltage. Cg is cell geometric capacity.
We propose that generated charges partly exist at electrodes and in active layer as electron-hole
pairs and the fast charge exchange take place between pairs and electrodes. The fraction of the
bound charges in pairs increases and average distance between positive and negative charges
decreases markedly at direct voltage. This causes the observed growth of capacity.
185
A COMPARISON OF THE PHOTOPHYSICAL PROPERTIES
OF CADMIUM CHALCOGENIDE NANOPARTICLES
SYNTHESIZED BY VARIOUS METHODS
V.Yu. Gak1, D.Yu. Nikolenko1, S.B. Brichkin1,
V.F. Razumov1, M.A. Zaporozhets2
1 - Institute of Problems of Chemical Physics RAS
2 - Institute of Microelectronics Technology and High-Purity Materials RAS
gak@icp.ac.ru
Various application areas of luminescent probes such as fluorescent tomography, requires to
develop a contrast luminescent labels. One of the most perspective objects for this aim are AIIBVI
semiconductor nanoparticles (NPs). The main methods of obtaining of monodisperse
semiconductor NPs of specified size with both spherical and anisotropic shape are hightemperature colloidal synthesis and synthesis in the reverse micelle (RM) solutions. RMs act
here as nanoreactors with controllable size and shape.
Cadmium chalcogenide (CdX, X=Se, S) NP of various size and shape were synthesized in the
sodium bis(2-ethyl-hexyl)sulfosuccinate (AOT) RM solutions, using cadmium nitrate, sodium
sulfide and pre-synthesized sodium selenosulfate (Na2SeSO3) water solutions as precursors and
n-heptane as a dispersion medium. The characteristic size of NPs was controlled by varying
w0=[H2O]/[AOT] value, defining RM water pool diameter. For further research NPs were
passivated by dodecanethiol. Aspherical CdS nanoparticles are synthesized in RM solution under
ultrasound treatment during all the time of its formation. The essence of essence of the method
consists in the reorganization of RMs under ultrasound irradiation and the subsequent
aggregation of the NPs into rod-like structures.
CdX NPs were also obtained by the method of high-temperature colloidal synthesis under
conditions of ‘‘size distribution focusing’’ due to controlled decrease of temperature, by
injection of trioctylphosphine-chalcogene complex into trioctylphosphine oxide (TOPO),
hexadecylamine, stearic acid or their mixture. In order to synthesize anisotropic NPs of CdSe at
first a synthesis of sphalerite structure nanoparicles in stearic acid was performed. Then these
NPs were transferred into TOPO/stearic acid mixture where wurtzite structure CdSe is formed in
such conditions. As a result of this synthesis the tetrapod-shaped CdSe NPs have been obtained.
In the present work a comparative study of CdX NPs, received by these two methods, has been
performed by the methods of transmission electron microscopy (TEM), steady-state absorption
and luminescent spectroscopy, and time-resolved laser fluorescent spectroscopy. The
luminescence decay curves of CdX NPs are non-monoexponential and the best fit may be
obtained with three-exponential law.
On the basis of the obtained spectral and kinetic data of nanorods it is possible to draw a
conclusion about mechanism of luminescence of CdS NPs synthesized by these method. In
reverse micelle synthesized In the particles synthesized in reverse micelles it has a trap
mechanism, while for the NPs obtained by the method of high-temperature colloidal synthesis
prevails aa band-gap one. Changes in the absorption, luminescence and excitation spectra of
samples received under the influence of ultrasound, can serve as signs of formation of nanorods.
This work is financially supported by Program of Fundamental Research RAS No. 27 “Basic
fundamental research in nanotechnology and nanomaterials”, and Russian Foundation for Basic
Research (project № 07-03-00397).
186
INVESTIGATION ON THE POSSIBILITY OF COVERING
CYANINE DYE J-AGGREGATES WITH SILICA SHELLS
A.V. Ivanchikhina
Moscow Institute of Physics and Technology
and Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
Ivanchihina@gmail.com
J-aggregates have attracted the interest of several research groups, due to their peculiar spectral
properties which make them potential candidates for applications in biology, as e. g. fluorescent
labels. The preparation of monodispersed nanometer-sized J-aggregates is of great practical
importance for this purpose. One of possible ways of solving this problem seems to be the use of
reverse micelles.
Moreover, an additional stabilization of J-aggregates is necessary to isolate them from micellar
solutions. Protecting J-aggregates by silica shells is suggested. Reverse micelles based on
polyoxyethylene (5) nonylphenyl ether (NP-5) are known to be used for capsulation of different
nanoparticles and dye molecules in silica. However there is no literature data on preparation of Jaggregates in NP5 reverse micelles.
We have studied (for the first time) the behavior of J-aggregates of a cyanine dye, 3,3’-di-(γsulfopropyl)-4,5,4’,5’-dibenzo-9-ethylthiacarbocyanine betaine pyridinium salt, in NP5/water/
cyclohexane reverse micelles within the range of W (W=[H2O]/[NP5]) from 3.1 to 8.3.
Since there is no any exact dependence of RM size on W for NP5, so hydrodynamic radii have
been measured by DLS for W = 3.1 ÷ 8.3.
We have worked out the method of dye micellar solution preparation that gives reproducible
results and permits to get maximum J-aggregates of minimal sizes. As-prepared RM solutions
contain the dye mainly in the J-aggregate form with a small amount of trans-monomers in the
whole range of W. Further evolution of absorption spectra is markedly different for different W.
For micellar solutions with W = 3.1 ÷ 4.0 there is a dye transition from J-aggregate form to
trans-monomer one and precipitation of J-aggregates located in cyclohexane during the whole
observation period (24 h). For W = 4.2 ÷ 8.3 the intensity of J-band increases during about 3
minutes and then decreases owing to the precipitation of J-aggregates located not in the water
pool. Moreover, for the whole range of W the higher the W (the smaller concentration of NP5
molecules and the larger RM sizes), the lesser amount of precipitated aggregates.
Taking into account that the largest amount of J-aggregates is in RM water pools at W=6,3, it
was just the value of W that was used for preparation of silica nanoparticles. A mean particle
diameter is 30 nm, standard deviation is 1 nm. As ammonia was used as catalyst for praparation
of SiO2 nanoparticles, its influence on J-aggregates behavior in RMs and properties of final SiO2
particles has been studied. The intensity of the J-band it was shown to decrease twice after a 24-h
when 2% aqua ammonia solution used as dispersed phase.
The obtained data show NP5/water/cyclohexane to be suitable for capsulation of dye Jaggregates by silica shells.
This work is financially supported by Program of Fundamental Research RAS №27 “Basic
fundamental research in nanotechnology and nanomaterials”.
187
THE LUMINESCENCE OF POLYMER COMPOSITE MATERIALS
WITH CdS NANOPARTICLES
V.I. Kochubey, Ju.G. Konyukhova, I.V. Zabenkov
Saratov State University, Russia
kochubey@optics.sgu.ru
The structure and the optical characteristics of CdS nanoparticles synthesized in high-pressure
polyethylene were examined. The synthesis was carried out by means of high-temperature
decomposition of precursors in the melt of polyethylene under argon atmosphere.
The structure of the nanoparticles was investigated by RFA and EXAFS methods. It is shown
that the particles have a greenockite-type hexagonal structure. The presence of cubic phase in the
small concentration is also possibly. From the EXAFS spectra obtained at room temperature, it
was drawn a conclusion that the disordereding degree of the cadmium ion environment decreases
in the nanoparticles in comparison with the macroobjects.
In view of the strong light scattering in the specimens the calculation of coefficients of
absorption and scattering by the method of inverse adding-doubling was carried out. The films
with a thickness of 60-150 µm were formed, and spectral measurements of complete
transmission, diffuse reflection and collimated transmission were conducted. It follows from the
obtained data that the position of the edge of absorption in the specimens weakly depends on
average size of nanoparticles. This can be explained by the significant polydispersion of the
nanoparticles.
It is shown that the luminescence spectra of the specimens are distorted strongly as a result of
scattering and self-absorption of luminescence inside the specimen. To correct the experimental
spectra, the simulation program by the Monte Carlo method of the process of the propagation of
luminescence in a specimen was constructed. It is shown that in the corrected spectra the shift of
the maximum of the luminescence band into the short-wave spectrum region occurs. In this case
the dependence of the maximum position on the precursors used and on the temperature of
synthesis was discovered.
The work partially supported by RFBR Grants №08-02-00404-а and №09-03-00369-а.
188
PHOTOELECTRIC NONLINEAR OPTICAL AND PHOTOREFRACTIVE
PROPERTIES OF COMPOSITES FROM POLYVINYLCARBAZOLE AND
SINGLE-WALLED CARBON NANOTUBES
T.V. Krivenko1, L.Ya. Pereshivko1, A.D. Grishina1, V.V. Savelyev1,
R.W. Rychwalski2, A.V. Vannikov1
1 - A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
2 - Department of Materials Science and Engineering,
Chalmers University of Technology, Göteborg, Sweden
van@elchem.ac.ru
The nonlinear optical properties, photoelectric and photorefractive (PR) sensitivities at 1064 and
1550 nm in the polymer composites from polyvinylcarbazole (PVK) doped with unoxidized and
oxidized single-walled carbon nanotubes (CNT 0.26 wt.%) as spectral sensitizers and nonlinear
optical chromophores were investigated. The third order optical nonlinearity was estimated by
electric field induced second harmonic method at content of SWCNT 0.26 wt.%. The pulse
Nd:YAG laser was used. Susceptibility is about 2×105 pm2/V2 or 2.3×10–29 Coulomb4×m/J3 (SI).
The photoelectric and PR properties were measured at 1064 and 1550 nm with using the
continuous wave lasers Nd:YAG (λ = 1064 nm) and IS550-120 (λ = 1550 nm). The quantum
efficiency of charge carrier generation as a function of the applied field was estimated from the
corresponding dependence of the photocurrent. The experimental values of the quantum
efficiency measured at 1064 nm and 1550 nm coincident and fit Onsager equation expanded up
to (E0)4. Experimental curves correspond to quantum yield of electron - poles pairs charge ϕ0 =
0.012 with the initial separation radius r0 = 9.8 Å. It was established that photoelectric and PR
properties does not react on the fullerene C60 adding. The principal PR characteristic is the gain
coefficient Γ that was measured at equal intensity of the input beams I1(0) = I2(0). The net gain
coefficient of object beam i.e. difference Γ – α has practical importance. Here α is the optical
absorption coefficient equals 10 and 3.3 cm–1 at 1064 and 1550 nm, respectively. The gain
coefficient of the signal beam equals Γ = 65 cm-1 at E = 170 V/µm and 1064 nm. At 1550 nm the
net gain coefficient equals Γ – α = 59 cm-1 in the field of E = 265 V/µm. It was established that
the addition of the fullerene C60 increase the gain coefficient of composites based on the
unoxidized SWCNT but have not effect on the composites containing oxidized CNT. This
difference may be conditioned by corresponding increasing electron affinity of SWCNT. For
composites additionally containing fullerene C60 2 wt. % there was also examined the effect of
the preillumination (preliminary illumination of the whole layer with 633-nm light in region of
optical absorption of C60) on the PR characteristics at 1550 nm. It was established that the
preillumination increases the gain coefficient. It is assumed that the holes photogenerated during
preillumination fill deep traps, which impede hole transport in the absence of the preillumination.
This work was supported by the ISTC (Grant No. 3718) and RFBR (project 08-03-00125).
189
ZIRCONIA NANOPARTICLES AS NEW MODEL MATERIAL
FOR NANOPHOTONICS: EFFECTS OF SELF-ORGANIZATION
V.A. Lubenets, O.A. Gorban, I.L. Lyubchanskii,
I.A. Danilenko, T.E. Konstantinova
Donetsk Institute of Physics and Engineering NAS of Ukraine
matscidep@aim.com
Self-organization is a well known technique for producing photonic crystals, in particular on the
base of ordered colloid micro spheres [1]. Though a wide using of this method is limited by the
problem of developing a stretched zone without any defects, and a perspective of its use it is
directly connected with the development of physico-chemical bases of controlling the
organization of nano-sized systems. It’s very interesting here to use the method of selforganization of nano-sized oxide particles with a given phase composition and surface structure
to obtain ordered sufficiently large structures. Oxide nanopowders are good model objects to
study self-organization processes both as consolidation of individual weakly aggregated nanoparticles in a powder system and as their consolidation in nanostructured think films. We should
mention that not only a size factor is important here, for these materials such constituents as
structure, surface state and chemical interaction become essential.
This wark has been devoted to the investigation of the self-organization processes in a weakly
aggregated system of separate zirconia-based nano-particles as large as 31 nm in nanostructured films (8-20 µm in thickness) in film casting at a further drying and sintering.
There are used nano-powders of ZrO2-3%Y2O3 of quadrilateral phase synthesized by coprecipitation by chloride technology with the use of extremal influences at the stage of xerogel
hydrate forming [2]. By the results of X-ray diffraction analysis, the size of coherent scattering
fields for this powder is 31 nm, which is in an agreement with the electronic microscopy data. By
the methods of infra-red spectroscopy and visible spectrophotometry there were studied optical
properties of the material and the surface state and nature of active centers were estimated.
According to data obtained, the surface of such systems contains acid and basic centers of both
Lewis and Brensted types. It is shown that vibrations in the IR spectral region of 1000 – 7500
sm-1 correspond to hydroxyl groups of the surface and absorbed water, and the spectrum itself
shows a transparence of this material in the spectral band given.
To produce films of 20 mkm in thickness there has been developed a technology of tape casting.
Polyvinylbutheral was used as a binder. Film drying was done in a multistage mode at up to
1100°С; tape sintering was done at 1500°С at the rate of 3o/min. It’s shown that production of
thin large ceramic films with a good surface is possible. By scanning electron microscopy there
was studied the surface of these films. It was shown that a sintered ceramic film is characterized
by a good homogeneous surface and has an average grain size up to 300 nm. There are discussed
optical properties of a ceramic film in the above mentioned IR region.
Thus, there was studied a possibility of using thin-tape casting technology for manufacturing
separate fragments of a 1-D photonic crystal with needed geometrical parameters.
1. В.I. Belotelov, А.К. Zvezdin Photonnye crystal I drygie materialy. М.: Byuro, 2006. – 144 с.
2. Т.Е. Константинова, И.А. Даниленко, В.В. Токий, В.А. Глазунова Получение
нанодисперсных порошков диоксида циркония. От инновации к инновации. // Наука и
инновации. 2005. Т1. №3. С.76 – 87.
190
LIGHT EMITTING AND OPTICAL PROPERTIES OF SILICON-RICH
SILICON NITRIDE AND SILICON-RICH SILICON OXIDE FILMS
T. Nikitin1, L. Khriachtchev1, S. Novikov2, M. Rasanen1
1 - Laboratory of Physical Chemistry, University of Helsinki, Finland
2 - Electron Physics Laboratory, Helsinki University of Technology, Helsinki, Finland
timur.nikitin@helsinki.fi
Silicon-based nanostructures have attracted a lot of attention over past two decades due to their
peculiar optical properties and promises in numerous optoelectronic applications. [1] Especially
the origin of 1.5 eV photoluminescence (PL) is still under intense debate. [2]
We studied silicon-rich silicon oxide (SRO) and silicon-rich silicon nitride (SRN) films on silica
or silicon wafer and free-standings films by means of Raman and PL spectroscopy, XPS and
TEM methods. Optical properties were measured using PL filtering effect in absorbing films. [3]
Reactive silicon deposition and ion implantation methods were used to fabricate thin films with
varied silicon concentration. Thermal annealing produces silicon nanocrystals in the film
material evidenced by Raman band at ~520 cm-1 and causes strong PL at ~1.5 eV.
As a result we compared (1) SRO films with different Si amounts, (2) SRO and SRN films (i.e.
containing and non-containing oxygen samples), and (3) SRO films prepared by two deposition
techniques: reactive silicon deposition and ion implantation. Based on these results we discuss
mechanisms of the PL and optical properties of our samples.
We acknowledge R. Velagapudi and J. Lahtinen for the XPS data. The present work was
supported by the FinNano Project “Optical and Surface Properties of Nanoparticles” (OPNA)
[1] Silicon nanophotonics: Basic principles, present status and perspectives, edited by L.
Khriachtchev (World Scientific, Singapore, 2008)
[2] L. Khriachtchev, T. Nikitin, R. Velagapudi, J. Lahtinen, and S. Novikov, Appl. Phys. Lett.
94, 043115 (2009)
[3] L. Khriachtchev, T. Nikitin, C. J. Oton, R. Velagapudi, J. Sainio, J. Lahtinen, and S.
Novikov, J. Appl. Phys. 104, 104316 (2008)
191
CLUSTERING OF CADMIUM TELLURIDE QUANTUM DOTS
IN A WATER SOLUTION IN THE PRESENCE OF METAL IONS:
THE ABSORPTION AND LUMINESCENT ANALYSIS
A.O. Orlova, A.V. Savelyeva, M.V. Mukhina,
V.G. Maslov, A.V. Baranov, A.V. Fedorov
St.Petersburg State University of Information Technologies, Mechanics and Optics, Russia
a_v_fedorov@inbox.ru
Fabrication of the nanostructures with desired optical properties is the topical problem of
nanoindustry. Semiconductor quantum dots (QDs) with characteristic sizes in order of several
nanometers have appeal us the building-blocks for creating of the nanostructures using, e.g., selforganization processes in a liquid solution [1]. It is significant that due to the spatial confinement
effect in QDs their optical properties are controlled by changing of the QD size [2]. Hence the
optical properties of the nanostructures based on QDs can be changed too. Furthermore the
possibility exists of for modifying of the optical characteristics of QDs and QD based
nanostructures by a variation of type and charge of a molecular shell covering QD surface as a
rule. The interesting nanostructures with some of the unusual optical properties are the clusters
containing various numbers (from several units to several thousands) of QDs ordered in some
extent or another. The clusters can arise as a result of spontaneous aggregation of QDs in liquid
solutions. Growth of the clusters in size is generally uncontrolled and it results in their settlingout finally. Important problem is the determination of conditions for formation of the sufficiently
stable clusters with certain size. It is desirable for the clusters to possess the properties that are
significant for applications, e.g., the property of photoexcitation energy transfer from the cluster
periphery to its center [3].
In present work an investigation of aggregation dynamics of the negatively charged CdTe QDs
in a water solution in the presence of Pb2+ and Cr3+ has been performed by means the absorption
and luminescent analysis included the measurements of decay times of the QD luminescence. It
has been shown that the stable clusters with certain size arise in the presence of Pb ions. The
photoexcitation energy transfer has been observed for the clusters of this type.
1. V.I. Roldugin, Russian Chemical Reviews 73,125 (2004).
2. A.V. Fedorov, A.V. Baranov, Optics of quantum dots. In book: Optics of nanostructures. Ed.
A.V. Fedorov. Saint-Petersburg, Nedra, 2005, P. 181-274.
3. A. Sukhanova, A.V. Baranov, T.S. Perova, J.H.M. Cohen, I. Nabiev, Angew. Chemie Int. Ed.
45, 2048 (2006).
192
SILICA NANOPARTICLES MODIFIED BY PYRYLOCYANINE DYE
WITH EFFECTIVE LUMINESCENT RESPONSE
N.A. Orlova1, I.Yu. Kargapolova1, V.V. Shelkovnikov1, A.I. Plekhanov2
1 - Novosibirsk Institute of Organic Chemistry SB RAS, Russia
2 - Institute of Automation and Electrometry SB RAS, Novosibirsk, Russia
vsh@nioch.nsc.ru
Polymethine dyes with electrophilic heterocycle are able to form covalent bond with nucleophile
that makes possible their use for formation of luminescent chemical and biochemical labels.
Especial interest have the polymethine dyes with pyrylium heterocycle forming the luminescent
pyridocyanines at soft reaction conditions.
The directed synthesis of functionalized pyrylocyanines to obtain the dyes connected with silica
nanoparticle frame was carried out in the research. The method of modified silica nanoparticles
formation with high concentration of functional dye is considered.
The samples of films with silica particles modified by 4-(4'-(2''-hydroxy-3''methoxypropoxy)styryl)-2,6-dimethylpyrylium perchlorate (1) were obtained and the reaction
with buthylamine solution was studied.
OH
O
CH=CH
OH
CH2-CH CH2OMe
O
CH=CH
CH2-CH CH2OMe
MeNH2
Me
O
ClO4
1
Me
EtOH, 20oC
Me
N
Me
Me ClO4
2
The formation of N-alkylsubstituted pyridocyanine fluorophore on the modified silica
nanoparticles was shown. The scheme of model reaction of pyridocyanine fluorophore 2
formation is shown above. The fluorophore formed on the silica nanoparticles has the green-blue
luminescence with maximum at 484 nm. The initial silica nanoparticles modified by
pyrylocyanine dye have in films the red-orange luminescence with maximum at 586 nm. The
samples of pyrylocyanine dye connected with silica nanoparticles have good photostability.
The research was practically supported by Russian federal agency science and innovation, grant
№02.513.11.3167.
193
COMPARISON STUDY OF THE NONLINEAR OPTICAL PROPERTIES
OF MOLECULAR J- AND H- AGGREGATES IN THIN SOLID FILMS
A.I. Plekhanov1, A.I. Gorkovenko1, N.A. Orlova2,
A.E. Simanchuk1, V.V. Shelkovnikov2
1 - Institute of Automation and Electrometry SB RAS, Novosibirsk, Russia
2 - Novosibirsk Institute of Organic Chemistry SB RAS, Russia
fractal@iae.nsk.su
The interest to the optical and nonlinear optical properties of organic molecular aggregates
determined by possibility of the application of organic nanostructures in modern optoelectronic
technologies. It is known that such structures possess the giant nonlinearity (χ(3)~ 10-5 esu) with a
subpicosecond relaxation times at a resonant condition [1] compared with other organic system.
High nonlinear-optical response of aggregated dyes and preparation technique based on selfassembly of dyes make these mediums perspective for optical modulations [2,3]. The most
attention is given to the optical and nonlinear optical properties of J- aggregates.
At the same time the studies of molecular H-aggregates are limited the questions of synthesis and
optical properties. We have studied and compared the dispersion of nonlinear absorption
coefficient of the molecular J- and –H-aggregates within the exciton absorption bands in spectral
range 645-670 nm at first time.
Thin films of J- and H-aggregates were prepared by spin-coating dye solution of
thiacarbocyanine dye BT-C18-H for J-aggregates and styryl type thiaflavylium dye DT-3 for Haggregates on 1 mm glass substrate and had exiton absorption bands at 645 nm and 670 nm,
respectively. The thickness of the samples was measured by spectral ellipsometry technique and
was about 10 nm. The optical density of the samples was about 0.3-0.4 at the exciton absorption
band.
The study of nonlinear optical properties was carried out with Z-scan open aperture technique.
We have used an optical parametric oscillator (“Solar”) with 15 ns pulse duration as a source of
radiation. The sensitivity of our experimental setup allowed measuring the relative bleaching of
0.5 %. The nonlinear absorption coefficient measurements were carried out in 625-690 nm
spectral range for both types of the samples. We have measured the dispersion of nonlinear
absorption coefficient of the thin solid films of molecular J- and –H-aggregates. The nonlinear
absorption coefficient at the exciton band maximum for J-aggregates turned out to be β = -90
cm/kW (saturation intensity Is = 3.5 МВт/см2) and β =-100 см/кВт (Is = 7 МВт/см2) for Haggregates. Taking into account the difference of the excitonic band widths we have concluded
that the nonlinear optical response of different types of the aggregated samples are the same
order of magnitude. In both cases of the J-aggregates and H-aggregates samples the frequency
dependence of the nonlinear absorption coefficient had found to be narrow than linear absorption
that is in a good agreement with the theoretical model of two level system.
1. R.V Markov., P.A.Chubakov, A.I.Plekhanov, et al., Nonlinear Optics. 2000 v.25, p. 365.
2. Kuch'yanov A.S., Markov R.V., Plekhanov A.I., Simanchuk A.E., Avdeeva V.I., Shapiro
B.I., Slominskii Yu.I., Tolmachev A.I., Optics Communs. 2004. v. 231, p.343.
3. M. Furuki, S. Tatsuura, O. Wada, M. Tian, Y. Sato, L. S. Pu. IEICE Trans. Electron. 2000.
E83-C, p.974.
194
LARGE ANGULAR DISPERSION EXPERIENCED
BY A LIGHT BEAM IN PASSING THROUGH THE BOUNDARY
OF A GLASS SUBSTRATE – PHOTON CRYSTAL
A.I. Plekhanov, A.A. Zabolotskii, A.S. Kuchyanov
Institute of Automation and Electrometry SB RAS, Novosibirsk, Russia
fractal@iae.nsk.su
Photonic crystals (PhC) [1] have inspired a lot of interest due to their potential for controlling the
propagation of light. The most of PhC applications are based on the use of their photonic band
gap. There are other applications based on the anomalous dispersion behavior of PhC, named the
superprism effect [2]. In the experiment [3] the PhC was fabricated by depositing alternate layers
of amorphous Si and SiO2 on a patterned Si substrate having a hexagonal array of holes. Under
certain conditions the light path shows a drastic wide swing with a slight change of the incident
light angle owing to the strong modification of group velocity at 1,5 -µm- wavelength range.
We have found the effect of a strong angular dispersion (~3 nm/deg) if one shines a white light
(300-700 nm) on the boundary between a glass substrate and PhC film. In this case we have
observed two dispersed light beams. One of them leaves the PhC film and another reflects back
in a glass substrate. The PhC films are fabricated on a glass substrate (with n =1.51) in a
suspension of SiO2 by dynamic meniscus method [4]. We have found the following features of
the effect that differ from the "superprism" effect.
In our case we have not observed any refraction when the radiation incident on the surface of a
PhC film at any angle from air. We have found that the extremely large angular dispersion
experienced by a light beam when entering a PhC film from a glass substrate. In our case the
light path does not show a drastic wide swing with a slight change of the incident light angle.
The value of average angle of dispersed light beam varies only slightly. We have observed that
our effect is almost insensitive to a dielectric contrast in contrast to the superprism effect. We
have found the azimuthal anisotropy of the effect is due to a hexagonal packing of PhC layers.
Thus, for the first time the effect of the extremely large angular dispersion experienced by a light
beam was observed when a light beam incident on the boundary of a glass substrate - PhC film.
The effect was observed for a visible spectral range. The observed phenomenon is due to
effective optical diffraction on PhC planes when a light beam is propagating in an optical dense
(glass) substrate in which the wavelength of light is less by a factor n.
This study was supported by the integration project of the SB RAS №17 and by the Program № 8
of Physical Sciences Division of the RAS.
1.
2.
3.
4.
E. Yablonovich. Phys.Rev.Lett. 1987, vol. 58, p.2059.
H. Kosaka, et. al., Phys. Rev. B, 1998, vol. 58, p.10096.
H. Kosaka, et al. J. Lightwave Technol. 1999, vol. 17, p.2032.
А.И. Плеханов, Д.В. Калинин, В.В. Сердобинцева. Российские нанотехнологии,
2006, т.1, №1, с. 245.
195
PHOTONIC BAND GAP IN PHOTONIC CRYSTAL
FORMED BY THE HOLOGRAM
A.S. Shcheulin, A.E. Angervaks, A.K. Kupchikov, A.I. Ryskin
St.Petersburg State University of Information Technologies, Mechanics and Optics State
University of Information Technologies, Mechanics and Optics, Russia
angervax@mail.ru
For a multi-layer slab that consists of layers of (a – d) and d thickness and ε and (ε + ∆ε)
dielectric susceptibility, respectively, homogeneous in the xy plane and alternating in z direction
(a model of 1D photonic crystal), the ratio of photon band gap width, ∆ω, to its average value,
ωm,
∆ω ∆ε sin (πd / a )
≈
⋅
.
(1)
a
ωm
ε
The ratio (1) is valid for small ∆ε and d/а values. It is evident from (1) that for 1D photonic
crystal the band gap do exist for any small values of two above-mentioned parameters. We have
observed this gap in the space distribution of optical radiation of the fluorescent 1D photonic
crystal formed by hologram written in the CaF2:Na crystal. The as-grown crystal was annealed in
the reduction atmosphere of the calcium vapors (an “additive coloration” procedure). As a result
of this procedure various color centers are formed in the crystal volume. The hologram was
written at high temperature in 18×10×12 mm specimen that was cut out of the colored crystal. At
the hologram writing optical properties of the crystal is modulated due to space modification of
the color center concentration. The subsequent illumination of the crystal with the appropriate
radiation transforms the most of the centers into the luminescent M A+ -centers (λmax = 760 nm).
The space frequency of the hologram was equal to 1/2 of the reciprocal wavelength of the
luminescence band maximum corrected for the crystal refractive index. Such specimen may be
considered as 1D photonic crystal, for which propagation of 760 nm radiation (wavelength in
vacuum) along the direction perpendicular to the hologram plane (xy) is forbidden due to
existence of the photonic band gap. The luminescence of the specimen was excited by He-Ne
laser radiation. The optical scheme allowed detecting the space distribution of the luminescence
at CCD camera plane, which was parallel to the hologram plane. A pit in the distribution
corresponding to z-direction (Fig. 1) shows the above
prohibition. The prohibition refers not only to the band
maximum but to an adjusting spectral range. The range
width, which is determined by a spectral selectivity of
the hologram, is relatively narrow as compared with
half-width of the luminescence band (~120 nm at room
temperature). Therefore, the pit has the relatively small
amplitude.
Figure 1. Distribution of M A -center luminescence in CaF2:Na
specimen with hologram at CCD camera plane. Numeralization of
x and y axes shows the corresponding pixel number.
+
196
STRUCTURAL ASPECT OF NANOPHOTONICS
OF FULLERENE SOLUTIONS
E.F. Sheka1, B.S. Razbirin2, A.N. Starukhin2, D.K. Nelson2,
M.Yu. Degunov2, P.A. Troshin3, R.N. Lyubovskaya3,
V.P. Fazleeva4, V.P. Gubskaya4, I.A. Nuretdinov4
1 - Peoples’ Friendship University of the Russian Federation, Moscow, Russia
2 - A.F. Ioffe Physical-Technical Institute RAS, St.Petersburg, Russia
3 - Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
4 - A.E. Arbuzov Institute of Organic and Physical Chemistry, Kazan RC RAS, Kazan, Russia
sheka@icp.ac.ru
The fullerene ability to form clusters in diluted solutions causes exciting spectral properties of
these matrices providing an enhancement of both the emission spectra and nonlinear optical
response [1-3]. Hereinafter, “fullerene” is related to both С60 and its derivatives. Being common
for solutions, the molecule clusterization and, as a consequence, a potential ability to use the
solution as an active nonlinear optical (NLO) matrix depends crucially from the fullerene
molecule chemical structure. When pursuing a goal of a selection of an NLO matrix with
required NLO characteristics, a researcher faces the problem of sorting a great number of
derivatives, both already available and newly to be synthesized. Obviously, the lack of a priori
criteria results in a considerable finance and time expenses. That is why the availability of a
reliable and, even more, a priori testing is of extreme importance.
The paper presents two ways of the problem solution based on empirical and computational
investigations [1-3]. In the first case, the testing reduces the problem to looking for an extra blue
emission in the visible part of spectra. The intense emission witnesses reliably good NLO
properties of the tested matrix. The second approach is based on quantum-chemical calculations
and can serve as a priori testing which can be followed afterwards by a synthesis of the fullerene
with required properties. The testing is based on the fact that the formation of stable clusters is
fully determined by the energy of pairwise interaction E cpl of fullerene molecules (sol-sol
clusters) and the fullerene and solvent molecule (sol-solv clusters). Stable clusters which enable
to provide the enhancement of the local electric field of both incoming and outgoing light are
formed if only Ecpl is negative and large by absolute value. The latter directly correlates with the
efficacy of the NLO response of the matrix considered. The two approaches are proven by
testing a set of matrices with different derivatives of fullerene C60, both already available and
purposely synthesized for the current study.
The work is financially supported by the RFBR (grants № 07-03-00755 and 08-03-01006).
References
1. B.S.Razbirin, E.F.Sheka, A.N.Starukhin, D.K.Nelson, P.A.Troshin, and
R.N.Lyubovskaya, JETP Lett. 87, 133-139 (2008)
2. E.F.Sheka, B.S.Razbirin, A.N.Starukhin, D.K.Nelson, L.N.Lyubovskaya , and
P.A.Troshin, JETP. 135, No.5 (2009)
3. E.F.Sheka, B.S.Razbirin, A.N.Starukhin, D.K.Nelson, P.A.Troshin, R.N.Lyubovskaya,
abd N.V.Kamanina, arXiv:0901.3728v1 26 January 2009.
197
MONODISPERSE POLYMERIC NANOPARTICLES
MODIFIED WITH CYCLODEXTRINS AND DYES
N.N. Shevchenko, A.Yu. Menshikova, I.V. Noskova,
B.M. Shabsels, A.V. Yakimansky
Institute of Macromolecular Compounds RAS, St.Petersburg, Russia
nata_non@hq.macro.ru
Recently, the inclusion compounds with dyes have attracted a great attention, since the dyes can
remarkably change their spectral features (absorption or emission) being included as the guest
molecules. So, cyclodextrins as host molecules can be used together with dyes to design novel
responsible materials for chemisensorics. The interior of cyclodextrins is considerably less
hydrophilic and able to host the most of hydrophobic dyes and hide them from aqueous media.
This approach was applied to attach some dyes to the surface of monodisperse polymeric
particles. One-step batch emulsion copolymerization of methyl methacrylate and Nvinylformamide (NVF) initiated by 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride in
the presence of α-, β-, or γ-cyclodextrins as a surface modifiers was applied to obtain
monodisperse particles. These particles had both positive surface charge and quite hydrophilic
surface. Variation in the concentration of cationic initiator, temperature, and pH of reaction
mixtures allowed preparing monodisperse latexes with particle diameters in the range of 220-270
nm and their mean-root-square deviation below 2%. To diminish the particle size down to 50 nm
a cationic surfactant, cetyltrimethylammonium bromide, was added in the reaction mixtures.
After rinsing by dialysis or successive centrifugation/redispersion in pure water, the surface of
obtained particles was hydrolyzed in acidic media. As a result, particle surface coated by grafted
cyclodextrin molecules also contained amino groups originated from NVF units along with
carboxylic groups from hydrolyzed initiator residues. The ζ-potential of all obtained particles
had the high positive values in the wide pH range.
In dialyzed dispersions of nanoparticles (100 nm in diameter) the formation of periodic colloid
structures was observed. It was exhibited as iridescence of the separate ordered structures with
the cross-section square of ~5 mm2. The particles of 250 nm in diameter was capable of selfassembling into periodic three-dimensional ordered structures, which demonstrated photonic
crystalline features.
Adsorption of Eosin, Fluorescein, or Rodamin 6G on the particle surface was investigated. The
changes in luminescence spectra of the dyes incorporated into particle surface in the presence of
acetone were revealed. This finding is a good promise for the usage of such particles modified
with cyclodextrins and dyes as sensor elements for chemisensorics.
The work is supported by the Federal Agency on Science and Innovation of the Russian
Federation (contract 02.513.12.3025) and by the Scientific Program “Basic research of
nanotechnology and nanomaterials” of the Presidium of the Russian Academy of Sciences.
198
RELATIONSHIP BETWEEN WATER VAPOR PRESSURE OF REVERSE
MICELLAR SYSTEM AND REVERSE MICELLES SIZE DISTRIBUTION
S.A. Tovstun, V.F. Razumov
Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
tovstun_sergey@rambler.ru
Multiple chemical equilibrium approach was used to derive an equation which relates reverse
micelles size distribution to their aggregation numbers and water vapor pressure above solution.
No assumptions about functional relations between surface tension and size or size and
composition have been used. Experimental data on reverse micellar solution of aerosol-OT
available in literature have been used to calculate the polydispersity with the aid of the equation
obtained. It was found that the polydispersity of aerosol-OT reverse micelles is in the range of 615%, depending on data used.
199
THE STUDY OF ENDOTAXIAL NANOSTRUCTURIZATION
OF POLY(3-HEXYLTHIOPHENE)/FULLERENE COMPOSITE
BY LIGHT-INDUCED ESR SPECTROSCOPY
E.I. Yudanova, V.I. Krinichnyi
Institute of Problems of Chemical Physics RAS, Chernogolovka, Russia
yudan@icp.ac.ru
Efficiency of polymer based solar cells is much higher when bulky heterojunctions of
interpenetrating nets of electron donor and electron acceptor materials are used. The most
promising compounds were found to be organic conjugated polymer - poly(3-hexylthiophene
(P3HT), and fullerene derivative – [1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61] (PCBM).
Photoinduced charge transfer in P3HT/PCBM bulky heterojunctions is accompanied by the
formation of a radical pair – polaron and a fullerene radical anion with S = ½. Therefore,
relaxation and dynamic properties of such paramagnetic centers can be investigated using lightinduced ESR spectroscopy (LESR). The ordered chain structure of P3HT can perform as a center
of nanostructurization of polymer molecules to two-dimensional layers via interchain alignment.
It was shown in [1] that self-organization of macromolecules upon regioregular P3HT
temperature annealing improves charge carrier mobility by more than two orders of magnitude.
However, nanostructurization can essentially be different in the starting polymer and in the
P3HT/PCBM composite matrix because of the effect of fullerene molecules on self-organization
of the polymer chains. The goal of this investigation was to study the effect of thermal
modification of the P3HT/PCBM composite on dynamic and kinetic properties of photoinduced
charge carriers.
The analysis of the magnetic, relaxation and dynamic parameters of polarons and fullerene
radical anions induced in the bulky heterojunction of the starting P3HT/PCBM composite and
the temperature annealing P3HT/PCBM composite by white light at different temperatures in a
wide (77 – 300 K) range showed that charges carriers in a radical pair do not interact. Thus, they
interact differently with their microenvironment. This allowed us to separately determine
magnetic, relaxation and dynamic parameters and identify the recombination and dynamics
mechanism for both types of charge carriers in the P3HT/PCBM bulky heterojunction. It was
shown that the interaction of polarons with the lattice is defined by its phonon energy, Eph, while
rotational diffusion of fullerene can be described in the frames of the Elliot model of activation
electron transfer through energy barrier, Eb. The calculation showed the Eph and Eb values to be
essentially lower after composite temperature annealing. The temperature dependences of
diffusion coefficients were calculated using polaron movement along and across polymer chains
and rotational diffusion of fullerene molecules. The decrease of anisotropy of polaron mobility
after thermal modification of the composite was found. This is evidence of higher effective
crystallinity of the polymer matrix. Composite heating provides nanostructurization of the bulky
heterojunction in the P3HT/PCBM composite as a result of the formation of fullerene and
polymer crystalline network and, hence, improves electronic properties of such plastic solar
cells.
1. Sirringhaus H., Brown P.J. et.al.// Nature,1999, v. 401, p.685-688.
200
ELECTROOPTICAL PROPERTIES OF POLARIZATION HOLOGRAPHY
GRATINGS IN POLYMER DISPERSED LIQUID CRYSTALS
G.M. Zharkova, S.A. Streltsov, A.P. Petrov, V.M. Khachaturyan
S.A. Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia
Zharkova@itam.nsc.ru
Liquid-crystal composites (LC-composites) present a polymer matrix, in its volume the capsules
of nematic liquid crystals (NLC) are dispersed. Polarization holographic gratings were produced
in the LC-composites by exposing the liquid crystal-prepolymer syrup to a light pattern obtained
by superposition of two waves having orthogonal linear polarization. In this case, the phase
difference variation between two interfering beams results only in the variation of the NLC
polarization state. Since the NLC is able to orient toward the resulting field, after the exposure a
grating with repeating NLC-orientations forms in the polymer capsules.
Such composite materials are promising because of the possibility of a relative simple one-stage
technology of the optical record, long-time storage of the polarization state, which provides the
high polarization selectivity and the possibility to control their optical properties with an electric
field [1–2]. Electrooptical properties of such gratings depend on the LC-composite morphology,
its geometrical sizes, and parameters of the controlling electrical field.
The purpose of the work was to study experimentally the diffraction efficiency of the
polarization holographic gratings, their response time dependence on the geometrical parameters
of the LC-composite and controlling field parameters.
The radiation source during the polarization holographic grating record was a semi-conductive
laser with λ = 658 nm and power of 80 mW. The pre-polymer composition presented a mixture
of the NLC, acrylate monomer, binding component and a photo-initiating system. The grating
spacing was of 19 micrometers. The dependencies of the diffraction efficiency of the
polarization holographic grating on the controlling electric field strength were obtained at the
incidence of the linearly polarized light on the grating at the Bragg’s angle. The dependencies of
the turn-on times and relaxation times on the sample thickness and frequency of the controlling
electric field are presented. Calculation and experimental data are compared. It is shown that at
the same modes of control, the turn-on times of the studied grating are shorter than the turn-on
times of the polymer liquid-crystal diffraction grating [3], which is caused by the better stability
of the formed structure of the LC-composite at the record of the polarization holographic grating
Reference:
1. G.P. Crawford, J.N. Eakin, M.D. Radcliffe, A. Callan-Jones, R.A. Pelcovits .Liquid-crystal
diffraction gratings using polarization holography alignment// J. Appl. Phys. – 2005, vol. 98,
p.123102.
2. A.Y.-G. Fuh, C.-R. Lee, C.-T. Cheng. Fast optical recording of polarization holographic
grating based on an azo-dye-doped polymer-dispersed liquid crystal film// Jap. J. Appl. Phys. –
2003, vol. 42. – pp.4406-4410.
3. G. М. Zharkova, А. P. Petrov,.В. I. V. Samsonova, S. А. Strel’tzov, V. М. Khachaturyan.
Polarization characteristics of the polymer liquid-crystal gratings // The Optical Journal. –
2008, Vol. 75, No. 8. – pp.48–52.
201
INDEX
Abakumov G.A. ..................................................... 117
Adamov G.E. ......................................................... 121
Adamova D.A. ....................................................... 121
Adrianov V.E. .......................................................... 70
Afanasiev A.V. ........................................................ 15
Ageev L.A................................................................ 90
Aiboushev A. ........................................................... 16
Aimukhanov A.K. .................................................... 57
Ait A.O. ........................................................... 79, 122
Ajiki H. .................................................................... 20
Akimkin T.M. ................................................ 118, 123
Alekseeva V.I. ......................................................... 58
Alexandrov A.P. ...................................................... 15
Alexeenko Yu.S. ...................................................... 76
Alfimov M.V.43, 47, 56, 61, 74, 78, 95, 148, 161,
166, 170
Andreev A.S. ......................................................... 124
Angervaks A.E. ...................................................... 196
Anisimov A.V. ................................................. 62, 156
Antipin V.A. ...................................................... 45, 66
Arabei S.M. ............................................................ 137
Arslanov V.V. ........................................................ 156
Artemyeva E.S. ...................................................... 125
Artyukhov V.Ya. ....................... 35, 94, 127, 128, 142
Astafiev A. ............................................................... 16
Avakayn V.G. .......................................................... 95
Avilov A.S. ............................................................ 183
Babenko S.D. ............................................. 77, 88, 185
Bagaturyants A.A. ................................................... 74
Balakai A.A. .......................................................... 185
Balakina M.Yu. .................................................. 46, 53
Barachevsky V.A. .............................. 79, 96, 122, 136
Baranov A.V. ........... 17, 19, 70, 80, 89, 130, 165, 192
Baranov D.A. ......................................................... 183
Barinov A.V. .................................................. 105, 106
Basilevsky M.V. ................................................ 47, 78
Basov L.L. ............................................................. 126
Batenkin M.A. ......................................................... 48
Baulin V.E. ........................................................ 49, 85
Bazyl O.K. ..................................................... 127, 128
Belikov N.E. .................................................. 131, 136
Belyakov L.V. .......................................................... 92
Berlin A.A................................................................ 79
Besugliy S.O. ........................................................... 73
Besuglui S.O. ........................................................... 76
Bikovskaya V.S. .................................................... 169
Bityurin N.M............................................................ 15
Bobyleva A.V. ....................................................... 156
Bodunov E.N. ........................................................ 129
Bogdanov G.N. ...................................................... 106
Bogdanova I.V. ........................................................ 34
Borisov A.V. ............................................................ 39
Borshchev O.V. ....................................................... 33
Brichkin S.B. ................................................. 164, 186
Budyka M.F. ............................................................ 97
Bugaychuk S. ..................................................... 22, 63
Bulanin K.M. ......................................................... 152
Butenin A.V. .......................................................... 132
Charushin V.N. ...................................................... 147
Che M. ................................................................... 144
Cherevkov S.A. ........................................................ 17
Chernyadyev A.Yu. ................................................. 50
Chernyshev A.V....................................................... 51
Chesnokov S.A. ............................................... 48, 117
Chibisov A.K. .......................................................... 98
Chizhov Yu.V. ............................................... 108, 124
Chmereva T.M. ...................................................... 110
Chubakov P.A. ....................................................... 173
Chubakov V.P. ....................................................... 173
Chumakov D.E......................................................... 62
Coluccia S. ............................................................. 144
Danilenko I.A......................................................... 190
Danilov V.V. .......................................................... 130
De Kok M. ............................................................... 36
Degtyarenko K.M. ....................................... 23, 54, 65
Degunov M.Yu. ..................................................... 197
Dembo К.А. ........................................................... 183
Demina O.V. .................................................. 131, 136
Denisov N.N. ........................................................... 24
Derkacheva V.M. ................................................... 132
Devadze L. ............................................................. 135
Dmitriev A.V. .......................................................... 69
Dmitrieva S.N. ....................................................... 161
Dorogan I.V. ............................................................ 76
Druzhinin A.V. ...................................................... 147
Druzhkov N.O........................................................ 117
Dubtsov S.N. ............................................................ 40
Dudar S.S. .............................................................. 180
Dultseva G.G. .......................................................... 40
Dushkin A.V. ..................................................... 32, 52
Dyachuk O.A. ........................................................ 143
Dzhagarov B.M........................................................ 99
Egorova A.V. ........................................................... 23
Eliseeva S.V. ............................................................ 82
Elyashevich G.K. ................................................... 130
Emeline A.V. ......................................... 100, 154, 155
Enakieva Yu.Yu. .................................................... 172
Eremina N.S. ................................................ 23, 54, 65
Ermolaev V.L......................................................... 180
Ermolaeva G.M........................................................ 92
Ermolina E.G. ................................................ 101, 137
Evseenko V.I............................................................ 52
Evseeva T.G. .................................................... 43, 170
Fazleeva V.P. ......................................................... 197
Fedorenko S.V. .................................................. 18, 30
Fedorov A.V. ......................... 17, 19, 70, 80, 165, 192
Fedorov Y.V. ......................................................... 156
Fedorova O.A......................................................... 156
Fedorova O.V......................................................... 147
Fedorova T.M. ....................................................... 132
Fedotov V.G........................................................... 175
Fominykh O.D. ........................................................ 53
Freidzon A.Ya........................................................ 161
Gadirov R.M. ............................... 23, 54, 65, 101, 133
Gaeva E.B. ............................................................... 51
Gak V.Yu. ...................................................... 164, 186
Galinovski N.A. ....................................................... 65
Garbovskiy Y. .......................................................... 22
Garbovskiy Yu. ........................................................ 63
German A.E. ............................................................ 90
202
Godovsky D.Yu. ...................................................... 55
Golubkov D.V.......................................................... 56
Gontareva N.B. ...................................................... 102
Gorban O.A............................................................ 190
Gorbunova Yu.G.................................................... 172
Gorelik A.M. .......................................................... 122
Goriuchko V.V. ..................................................... 115
Gorkovenko A.I. .................................................... 194
Goryachev A.E. ....................................................... 41
Goryachev N.S. .............................................. 105, 106
Gostev F.E. .............................................................. 38
Grebennikov E.P. ................................................... 121
Grigoriev F.V. .......................................................... 47
Grigoriev V.V. ....................................................... 106
Grishina A.D. ................................................. 172, 189
Grodzyuk G.Ya ........................................................ 83
Gromov S.P.............................................. 43, 161, 166
Gubin S.P. .............................................................. 183
Gubskaya V.P. ....................................................... 197
Gurinov A.A. ................................................. 150, 151
Gurinovich V.V. .................................................... 134
Hakina E.A. ............................................................. 84
Hoppe H. .................................................................. 41
Ibrayev N.Kh. .................................................... 57, 58
Iida T. ....................................................................... 20
Inganas O. ................................................................ 55
Ionov D.S. ................................................................ 61
Ishchenko A.A. ...................................................... 128
Ishihara H................................................................. 20
Ivanchikhina A.V. .......................................... 167, 187
Ivanov D.A. ............................................................. 56
Ivanov V.B. ............................................................ 104
Ivanova S.S. ........................................................... 137
Izmodenova S.V. ................................................... 168
Japaridze K. ........................................................... 135
Kalashnikova I.P. ................................................... 137
Kaliya O.L. ............................................................ 132
Kaplunov M.G. .................................................. 67, 87
Kargapolova I.Yu. ................................................. 193
Kashin A.S. ............................................................ 118
Kataeva G.V. ................................................. 154, 155
Kazakov V.P. ..................................................... 45, 66
Kazansky V.B. ....................................................... 103
Keshtov M.L. ........................................................... 59
Khachaturyan V.M. ....................................... 184, 201
Khakina E.A. ..................................................... 41, 60
Khamova T.V. ......................................................... 75
Khavina E.Yu. ....................................................... 104
Khlebunov A.A. ....................................................... 61
Khodonov A.A. .............................................. 131, 136
Khodos I.I. ............................................................. 183
Khoroshutin A.V...................................................... 62
Khrebtov A.I. ......................................................... 130
Khriachtchev L. ............................................... 21, 191
Kislov D.A. ............................................................ 110
Kispert L.D. ............................................................. 32
Klimusheva G. ................................................... 22, 63
Klinskikh A.F. ....................................................... 111
Kluyev V.G. ............................................................. 31
Klyuev V.G. ........................................................... 169
Knyukshto V.N. ....................................................... 93
Kobeleva O.I. ......................................................... 122
Kochubey V.I. ................................................ 143, 188
Koetse M.M. ............................................................ 36
Kol’tsova L.S. .......................................................... 91
Kolesnik I.N. ............................................................ 65
Kolesnikov M.P. .................................................... 119
Komarov P.V. .......................................................... 61
Konarev D.V. ........................................................... 60
Kondo T. .................................................................. 27
Kondracki B.A. ........................................................ 64
Konev A.N. .............................................................. 48
Konovalov A.I. .................................................. 18, 30
Konovalova O.D. ............................................... 18, 30
Konovalova T.A....................................................... 32
Konstantinov N.Y. ................................................... 49
Konstantinova T.E. ................................................ 190
Konyukhova Ju.G. ................................................. 188
Kopylova T.N. ............................... 23, 35, 54, 65, 133
Korolev V.V............................................................. 71
Korotkov V.I. ......................................... 146, 150, 151
Korovin Yu.V. ....................................................... 101
Koshkin A.V. ............................................. 43, 61, 170
Kosjakova E.A. ........................................................ 31
Kotelnikov A.I. .............................................. 105, 106
Kotelnikova R.A. ................................................... 106
Kotova O.V. ....................................................... 82, 85
Kovalev A.A. ..................................................... 45, 66
Krasnaya Zh.A. ...................................................... 158
Krasnikova S.S......................................................... 67
Krasnovsky A.A..................................................... 107
Krauklis I.V. .................................................. 108, 115
Krinichnyi V.I. ................................................. 24, 200
Kritsky M.S.................................................... 109, 119
Krivenko T.V. ................................................ 172, 189
Kruchinin A.U. ........................................................ 64
Kruchinin N.Y. ...................................................... 168
Kruchinin S.Yu. ............................................... 19, 165
Kruijt P.G.M. ........................................................... 36
Kryukov A.I. .......................................................... 179
Kucherenko M.G. .......................................... 110, 168
Kuchmiy S.Ya.................................................. 83, 179
Kuchyanov A.S. ............................................. 174, 195
Kukhta A.V. ............................................................. 25
Kukhto A.V........................................................ 23, 65
Kukhto I.N. .............................................................. 65
Kupchikov A.K. ..................................................... 196
Kurbangaleev V.R. ................................................ 121
Kurskii Yu.A. ......................................................... 117
Kuz’mina L.G. ....................................................... 161
Kuzicheva E.A. ...................................................... 102
Kuzmin G.N. .......................................................... 154
Kuzmina L.G. ........................................................ 166
Kuzmina N.P. ..................................................... 82, 85
Kuznetsova R.T. ............................................ 101, 137
Kvashnina N.V............................................... 111, 114
Kvyatkovskii O.E. ................................................... 92
Lachinov A.N..................................................... 45, 66
Laptenkov D.V....................................................... 138
Laptev A.V..................................................... 131, 136
Latyshev A.N. .......................................... 31, 111, 114
Leonova L.Yu. ......................................................... 31
Lepeshkevich S.V. ................................................... 99
Lepnev L.S. ........................................................ 82, 85
Leshina T.V. ............................................................ 32
Lesnichin S.B. ................................................ 150, 151
203
Levin P.P.......................................................... 91, 159
Lisachenko A.A. .................... 112, 126, 139, 140, 144
Litke S.V. ............................................................... 125
Lobach A.S. ............................................................. 87
Lobo R.F. ............................................................... 152
Logacheva N.M. ...................................................... 49
Logis A.G. ............................................................. 133
Loukova G.V. ........................................ 113, 141, 162
Lukin A.Yu. ................................................... 131, 136
Lukov A.V. ............................................................ 141
Lukovskaya E.V. ................................................... 156
Lukyanov B.S. ................................................... 76, 90
Lupicov D.I. ............................................................. 75
Lupikov D.I.............................................................. 68
Luponosov Y.N........................................................ 33
Lybenets V.A. ........................................................ 190
Lypenko D.A. ........................................ 26, 59, 69, 81
Lyssenko K.A. ......................................................... 82
Lyubchanskii I.L. ................................................... 190
Lyubovskaya R.N. ..................................... 60, 88, 197
Maiorova T.L. ........................................................ 169
Maisuradze D. ........................................................ 135
Maksimchuk N.V. .................................................... 39
Mal’tsev E.I. ............................................................ 81
Malkin V.M. .......................................................... 115
Maltsev E.I. .................................................. 26, 59, 69
Mamedov M............................................................. 38
Mardaleishvili I.R. ................................................... 91
Marinina L.E. ........................................................... 58
Marinov I.L. ................................................... 116, 153
Martra G................................................................. 144
Maskevich S.A. ................................................ 90, 178
Maslov V.G.................. 17, 70, 80, 146, 150, 151, 192
Maslova E.A. ......................................................... 115
Masuda H. ................................................................ 27
Masuhara H. ............................................................. 28
Matveeva A.G. ......................................................... 71
Mayer G.V. ........................ 23, 94, 101, 127, 137, 142
Medvedev E.S. ....................................................... 105
Melnikov A.G. ....................................................... 143
Melnikov G.V. ....................................................... 143
Menshikova A.Yu. ........................... 43, 170, 175, 198
Mensov S.N. ...................................................... 48, 72
Meshkov A.M. ....................................................... 146
Meshkova S.B. ......................................................... 23
Meteleva E.S. ..................................................... 32, 52
Metelitsa A.V. .................................................... 51, 73
Meulendijks N.N.M.M. ........................................... 36
Micheau J.C. ............................................................ 29
Mikhaylov R.V. ..................................... 138, 140, 144
Milov A.D. ............................................................... 42
Minakov D.A. ........................................................ 114
Minibaev R.F. .......................................................... 74
Minkin V.I. ........................................................ 51, 73
Mirnaya T. ......................................................... 22, 63
Mishchenko D.V. ................................................... 106
Mochalova A.E. ....................................................... 15
Molodid S. ............................................................. 177
Morozov V.A. ........................................................ 145
Moskvin Yu.L. ....................................................... 185
Movchan T.G. .................................................... 68, 75
Mukhanov E.L. ........................................................ 76
Mukhina M.V. ......................................... 19, 165, 192
Mustafina A.R. ................................................... 18, 30
Muzafarov A.M. .......................................... 33, 77, 84
Myshkovskaya E.N. ................................................. 77
Nadolinskaya S.S. .................................................. 146
Nadtochenko V. ....................................................... 16
Nadtochenko V.A. ................................................... 38
Nakaryakov A.S. ...................................................... 45
Naumova E.V......................................................... 143
Nazarov V.B. ........................................................... 95
Nelson D.K. ........................................................... 197
Nevidimov A.V...................................................... 171
Nikitin T. ................................................................ 191
Nikitina E.A. ...................................................... 47, 78
Nikolaichik V.I. ..................................................... 183
Nikolenko D.Yu. ............................................ 164, 186
Nikolenko L.M....................................................... 167
Nikonorova N.A....................................................... 43
Nikonov S.Yu. ....................................................... 133
Noskova I.V. .......................................................... 198
Nosova G.I. .............................................................. 43
Novikov S. ............................................................. 191
Nuretdinov I.A. ...................................................... 197
Odinokov A.V.......................................................... 78
Optov V.A. ............................................................... 79
Orlova A.O............................. 17, 70, 80, 89, 130, 192
Orlova N.A..................................................... 193, 194
Ortega J.M. ............................................................ 105
Os’kina O.Yu. .......................................................... 91
Ovchinnikov O.V. .................................................... 31
Ovchinnikova I.G................................................... 147
Ovtchinnikov O.V.......................................... 111, 114
Panova I.G. ............................................................ 159
Pavich T.A. ............................................................ 137
Peregudov A.S. .................................................. 41, 60
Peregudova S.M. ...................................................... 60
Perelygina O.M. ................................................. 26, 81
Pereshivko L.Ya............................................. 172, 189
Petrov A.P. ..................................................... 184, 201
Petrov N. Kh. ........................................................... 78
Petrov N.Kh. ............................................................ 56
Petrova E.G. ........................................................... 132
Pham Thi Hai M. ................................................... 169
Plachev Yu.A. .................................................... 34, 50
Plekhanov A.I. ............................... 173, 174, 193, 195
Pleshkov D.N. .......................................................... 82
Plotnikov V.G. ....................................................... 148
Plyusnin V.F. ........................................................... 71
Pokhodenko V.D.................................................... 179
Polushtaytsev Yu.V. ................................................ 72
Polyakov N.E. .................................................... 32, 52
Ponomarenko S.A. ....................................... 33, 77, 84
Poretskiy M.S......................................................... 149
Pozin S.I. ............................................................ 26, 59
Pravdin A.B. .......................................................... 143
Prokhorov V.V. ........................................................ 81
Pronkin P.G............................................................ 160
Raevskaya A.E. ........................................................ 83
Raitman O.A. ......................................................... 156
Rapoport V.L. ................................................ 108, 115
Rasanen M. ............................................................ 191
Rasshchepkina N.A.................................................. 86
Razbirin B.S. .................................................. 176, 197
Razumov V.F. ............................ 41, 88, 164, 186, 199
204
Rensing P.A. ............................................................ 36
Revina A.A. ............................................................. 34
Reznikov V.A. ......................................................... 71
Romanova V.S. ...................................................... 106
Rozhkova J.A. ................................................ 150, 151
Rudakova A.V. ...................................... 116, 152, 153
Rudyak V.Y. ............................................................ 95
Rusakova N.V. ....................................................... 101
Rusinov G.L. .......................................................... 147
Ryabchuk V.K. ...................................... 152, 154, 155
Ryashin O.N. ........................................................... 76
Ryazanov M.I. ....................................................... 182
Rybkin A.Yu. ......................................................... 106
Rychwalski R.W. ................................................... 189
Ryskin A.I. ............................................................. 196
Sabsai O.Yu. ............................................................ 79
Safiulina A.M. ......................................................... 49
Sagun E.I.................................................................. 93
Salazkin S.N. ..................................................... 45, 66
Samoilova R.I. ......................................................... 42
Samsonova L.G.......................................... 23, 35, 133
Sariciftci N.S............................................................ 41
Sarkisov O.M. .................................................... 16, 38
Savelyev V.V. ................................................ 172, 189
Savelyeva A.V. ........................................ 19, 165, 192
Savvina L.P. ............................................................. 58
Sazhnikov V.A. .......................................... 43, 61, 170
Sazonov S.K. ........................................................... 43
Schoo H.F.M. ........................................................... 36
Selector S.L............................................................ 156
Selivanov N.I. .......................................................... 35
Seliverstova E.V. ..................................................... 57
Selkin A.V. ............................................................ 175
Semenishin N.N. .................................................... 101
Semenov A.Yu. ........................................................ 38
Sepashvili N. .......................................................... 135
Shabsels B.M. ........................................................ 198
Shakhverdov T.A. .................................................. 157
Shcheulin A.S. ....................................................... 196
Sheka E.F. ................................................ 37, 176, 197
Shelaev I.V. ............................................................. 38
Shelimov B.N. ....................................................... 144
Shelkovnikov V.V. ........................................ 193, 194
Shenderovich I.G. .......................................... 150, 151
Sheremetyeva N.V. ........................................ 154, 155
Sherstiuk V. ........................................................... 177
Shevchenko N.N. ............................. 43, 170, 175, 198
Shilova O.A. ............................................................ 75
Shiyonok A.I. ........................................................... 91
Shmyryeva A.N. ...................................................... 39
Shul’gin V.F. ........................................................... 23
Shulgin V.A. .......................................................... 114
Shumilkina E.A.................................................. 33, 84
Shurygina M.P. ...................................................... 117
Shuvaev S.V. ........................................................... 85
Shvedova L.A. ....................................................... 158
Shvets V.I. ............................................................. 136
Simanchuk A.E. ..................................................... 194
Skubnevskaya G.I. ................................................... 40
Smagulov Zh.K. ....................................................... 58
Smirnov M.S. ........................................... 31, 111, 114
Smirnov N.N. ........................................................... 43
Smirnov V.A. ................................. 113, 141, 148, 162
Smirnova L.A........................................................... 15
Solodova T.A. .......................................................... 35
Soloveva E.V. .......................................................... 73
Solovjev V.S. ........................................................... 86
Solovskaya N.A. ...................................................... 43
Solovyov K.N. ....................................................... 137
Soulimenkov I.V. ..................................................... 60
Spirin M.G. ............................................................ 164
Spitsina N.G. ............................................................ 87
Starukhin A.N. ....................................................... 197
Stass D.V. ................................................................ 71
Strekal N.D. ........................................................... 178
Streltsov S.A. ......................................................... 201
Strikhanov M.N. .................................................... 182
Stroyuk A.L. .................................................... 83, 179
Stuchebrukhov A.A. .............................................. 105
Subbotina I.R. ........................................................ 103
Sultimova N.B. ...................................................... 159
Surin N.M. ................................................... 33, 77, 84
Susarova D.K. .................................................... 41, 88
Susarova S.D. ........................................................... 77
Suvalov V.A............................................................. 38
Suvorova T.I. ................................................. 111, 114
Sveklo I.F. ................................................................ 90
Sveshnikova E.B. ................................................... 180
Svetlichnyi V.A. .................................................... 128
Syl’yanov S.N. ....................................................... 183
Tameev A.R. .......................................................... 181
Tarasova N.A. ........................................................ 156
Tatikolov A.S. .................. 91, 118, 123, 158, 159, 160
Tedoradze M.G. ....................................................... 34
Telegina T.A. ......................................................... 119
Telminov E.N......................................................... 137
Tishchenko A.A. .................................................... 182
Titov V.V. .............................................................. 140
Tkachev V.V. ........................................................... 76
Tolochko A. ....................................................... 22, 63
Topilova Z.M. .......................................................... 23
Toporova Yu.A. ................................................. 17, 80
Tovstun S.A. .......................................................... 199
Troshin P.A. ..................... 41, 60, 77, 84, 88, 185, 197
Tsivadze A.Y. .......................................................... 49
Tsivadze A.Yu. .......................................... 50, 85, 172
Tsvetkov Yu.D. ........................................................ 42
Tsvirko M.P. .......................................................... 134
Tsyganenko A.A. ................... 116, 120, 149, 153, 163
Ukleev T.A............................................................. 175
Ushakov E.N. ................................................. 161, 166
Ushakova E.V. ............................................. 17, 19, 89
Usov N.N. ................................................................ 64
Utkina N.A. ............................................................ 130
Uzhinov B.M. .......................................................... 62
Van Heck G.T. ......................................................... 36
Vannikov A.V. ..................... 26, 69, 81, 172, 181, 189
Varfolomeev S.D. .......................................... 131, 136
Vasiliev V.P. .......................................................... 162
Vasilyuk G.T. ........................................................... 90
Vechtomova Yu.L.................................................. 119
Vedernikov A.I. ............................................. 161, 166
Vershinnikova T.G................................................... 95
Volkov A.V.............................................................. 86
Volkov V.V............................................................ 183
Voloshin N.A. .................................................... 51, 73
205
Von Borczyskowski C. ...................................... 44, 93
Vorobey A.V.......................................................... 134
Voronina K.V. ....................................................... 163
Wieringa F.P. ........................................................... 36
Yakimansky A.V. .................................... 43, 170, 198
Yakushchenko I.K. .................................................. 67
Yarmoluk S.M. ...................................................... 123
Yudanova E.I. .................................................. 24, 200
Zabenkov I.V. ........................................................ 188
Zabolotskii A.A. .................................................... 195
Zaichenko N.L. ........................................................ 91
Zakharova I.B. ......................................................... 92
Zaporohzets M.A. .................................................. 183
Zaporozhets M.A. .................................................. 186
Zemtsov R.V. ................................................. 131, 136
Zenkevich E.I. .................................................... 44, 93
Zharkova G.M................................................ 184, 201
Zhigalina O.M........................................................ 183
Zhokhova D.A. ...................................................... 106
Zhuravlev N.A. ........................................................ 74
Zolotarevsky V.I. ................................................... 172
Zvezdin K.V........................................................... 136
206
LATELY RECEIVED ABSTRACTS
SURFACE PHOTOVOLTAGE AND BAND ALIGNMENT
AT A HYBRID INTERFACE BETWEEN A CONJUGATED
ORGANIC OVERLAYER AND ZnO(0001) SURFACE
I.S. Busin, A.S. Komolov
Physics Department, St.Petersburg State University, Russia
akomolov07@ya.ru
Formation of interfaces in hybrid materials made from a metal oxide and an organic
semiconductor is usually accompanied by interfacial chemical reactions and this may be a route
for making new functional surfaces. There are known efficient photovoltaic devices based on the
interfaces between titanium dioxide and organic films [1,2]. The interface interaction could lead
to formation of the interface related electronic states, which could be observed as additional
peaks on the spectrum of the electronic structure of the organic films [3].
A few nm N,N-bis(3-methylphenyl)-N,N-bis(phenyl)-benzidine (TPD) overlayers were
thermally deposited in situ in UHV onto ZnO (0001) surface. Atomic composition of the
surfaces under study was monitored using Auger electron spectroscopy (AES). The formation of
the interfacial potential barrier and of the structure of the unoccupied electronic states located 525 eV above the Fermi level (EF) were monitored using a probing beam of low-energy electrons
according to the Total current electron spectroscopy (TCS) method.
The spectroscopic results showed that the electronic density was transferred over the interface
from the organic molecules to the ZnO (0001) surface. The electronic transfer was accompanied
by the modification of the peak structure of the unoccupied density of states of the TPD film
within a few nm thick layer. There was also found out that the surface potential of the TPD/ZnO
hybrid structure was sensitive to visible light excitation.
The major photovoltage response was observed within the excitation wavelength range from 360
nm to 600 nm, which corresponds to the quanta energies from 3.4 eV to 2 eV, approximately.
The higher excitation energies within this range correspond to energy gap values for the TPD
and ZnO materials under study. At the same time the photovoltage response at the excitation
energies from 2 eV to 3 eV should correspond to the sub-bandgap energy transitions. These
transitions involve the newly formed electronics states, which were formed upon formation of
the hybrid ZnO/TPD interface. A formation mechanism for these electronic states considering
the presence of the excess Zn atoms and the electronic dipole at the interface was suggested.
The work was supported by RFFI grants 08-03-00270 и 09-03-12010.
References:
[1] K.C. Kim, J.H. Park, O.O. Park, Solar Energy Materials and Solar Cells 92 (2008) 1188
[2] P. Suresh, P. Balaraju, S.K. Sharma, M.S. Roy, G.D. Sharma, Solar Energy Materials and Solar Cells.
92/8 (2008) 900.
[3] Braun S., Osikowicz W., WangY., Salaneck W.R. Organic Electr. 8 (2007) 14.
[4] Komolov A. S., Møller P. J., Mortensen J., Appl. Surf. Sci. 253 (2007) 7376
207
SENSITIZED LUMINESCENCE OF DOPED MOLECULAR
ORGANIC POLYCRYSTALS
N.A. Klemesheva1, S.S. Nadoliskaya1, J.A. Rozhkova1, E.P.Zarochentseva1,
S.O.Vysotskaja1, D.A.Kudrjavtseva2, A.A.Evstrapov2, V.I. Korotkov1
1 – Physics Department, St.Petersburg State University, Russia
2 – Institute for Analytical Instrumentation RAS, St.Petersburg, Russia
korotkov@paloma.spbu.ru
Doped molecular polycrystals are good objects for investigating of phenomena of electronic
excitation energy transfer owing to very close arrangement of host and quest molecules.
Therefore it is possible two mechanisms of energy transfer – exchange-resonance and inductiveresonance. Earlier we detected appearance of long−lived states and sensitized phosphorescence
in polycrystals of benzoic acid doped with bromated polyphenyls.
The present work is concerned with the phenomena of heavy atom and crystal structure influence
on sensitized luminescence of doped molecular polycrystals. Well known that heavy atoms
increase the probability of the triplet yield caused by the spin-orbit coupling. At the same time,
the introduction of heavy atoms into molecule almost does not change energy of the electronic
levels of molecules. In crystals, because of the close packing of molecules, both - internal and
intermolecular - heavy-atom effects are observed.
To make clear influence of crystal structure on excited states properties of quest molecules in the
doped molecular crystals we studied two host matrixes with different crystal structure and one
quest molecule. Matrix molecules contain heavy atoms Br.
The luminescent spectra of monobromated camphora (BC) and dibromobenzene (DBB)
polycrystals doped anthranilic acid (ANTR) have been investigated. Luminescence spectra of
BC doped ANTR at room temperature consist of long-wave emission, attributed to
phosphorescence. Spectrum is intensive and not resolved with one maximum at 450 nm.
Changing of guest concentration leads to shift position of maximum. Concentration growth from
10-4 to 10-1 M/M moves maximum position from 420 nm to 440 nm.
Phosphorescence excitation spectrum, detected at 425nm, has two maxima near 225 nm, and 365
nm. First band can be attributed to singlet-singlet absorption, second – to singlet-triplet (S0→T1)
absorption. The excitation spectra, detected at different wavelengths indicate that short-wave and
long-wave parts of phosphorescence spectrum have different excitation. The excitation spectra,
detected at 470nm show band with maxima at 225, 350 and 405 nm. Under detecting at 440 nm
long-wave maximum displaces to 380 nm, and under detecting at 425 nm maximum moves to
365 nm. There is a dependence of excitation spectrum versus guest concentration.
Phosphorescence excitation spectra of polycrystals with different guest concentration show
mixture of host (BC) and quest (ANTR) absorption spectra. Part of quest absorption increase
with increasing its concentration.
Therefore one can concludes that luminescence spectra of BC doped ANTR at room temperature
consist of superposition of host and quest molecules phosphorescence.
208
PHOSPHORESCENCE OF ORGANIC POLYCRYSTALS
AT ROOM TEMPERATURE
N.A. Klemesheva1, S.S. Nadoliskaya1, J.A. Rozhkova1, E.P.Zarochentseva1,
S.O.Vysotskaja1, D.A.Kudrjavtseva2, A.A.Evstrapov2, V.I. Korotkov1
1 – Physics Department, St.Petersburg State University, Russia
2 – Institute for Analytical Instrumentation RAS, St.Petersburg, Russia
korotkov@paloma.spbu.ru
The objective of this work is to investigate the influence of heavy atom and crystal structure on
the phosphorescence parameters and, in particular, the intersystem crossing rate constant. Since
an approach to this topic requires analysis of a large quantity of experimental phosphorescence
data 7 molecules were studied. To make clear influence of these factors on excited states
properties of molecules the luminescent spectra of solutions and polycrystals of αmonobromated camphora (BC), acenaphthenequinone (ACNQ), acetanilide (ACTN),
dibromobenzene (DBB), mellitene (GMB), triazole (TRZL), anthranilic acid (ANTR) has been
investigated.
Polycrystals of all investigated compounds exposed phosphorescence at room temperature.
Phosphorescence of all compounds excites by singlet-singlet and forbidden singlet-triplet
absorption. The main experimental parameters of the compounds studied are given.
Phosphorescence spectrum of ACTN is well resolved, maximum situates at 416 nm.
Phosphorescence excitation spectrum locates in spectral region 300-400 nm.
ACNQ has maximum of phosphorescence at 470 nm. Maximum of phosphorescence excitation
spectrum is situates near 355 nm.
Phosphorescence spectrum of TRZL is unresolved with maximum at 425 nm. Phosphorescence
excitation spectrum has two maxima: at 260 nm, corresponding to singlet- singlet (S0→S1)
absorption and at 370 nm, corresponding to (S0→T1) absorption.
ANTR exposes very intensive well resolved spectrum of phosphorescence with maximum at 450
nm. Broad phosphorescence excitation spectrum has two maxima near 320 nm, (S0→S1)
absorption and 400 nm, (S0→T1) absorption.
Phosphorescence spectrum of GMB has well resolved vibration structure, maximum situates at
470 nm. Phosphorescence excitation spectrum consists of two maxima near 220 nm, (S0→S1)
absorption and 355 nm, (S0→T1) absorption.
Low intensity phosphorescence spectrum of BC locates in broad spectral region 350-650 nm
with maximum at 472 nm. Phosphorescence excitation spectrum has two parts: short-wave
singlet- singlet absorption and long-wave singlet-triplet absorption.
DBB polycrystals exhibit resolved phosphorescence in the 340-650nm region at room
temperature. Spectrum has two maximums – 375 and 473 nm. Luminescence spectrum of DBB
solution is unresolved and has fluorescence maximum near 310 nm and phosphorescence
maximum at 470 nm. The excitation spectra, detected at different wavelengths indicate that
short-wave and long-wave parts of phosphorescence spectrum have different excitation. The
excitation spectra, detected at 375, 473 nm show well-resolved band corresponds to the singlettriplet (S0→T1) absorption. There is a dependence of structural properties of DBB fluorescence
excitation spectrum versus registration wavelength: the best resolution is observed at short-wave
registration near 0-0 transition. The excitation spectra, detected at 500, 550 nm corresponds to
the singlet- singlet (S0→S1) absorption. The crystals of DBB are monoclinic (a=15.36, b=5.75,
c=4.10 A) and belong to space group P21/a(C2h5) with two molecules per unit cell. Each allowed
molecular state should, therefore, have two allowed components, one polarized parallel to and
the other perpendicular to the b axis of crystal.
209
ELECTROLUMINESCENCE OF NONCONJUGATED
POLYARYLENEPHTHALIDES
V.A. Antipin1, A.A. Kovalev2, A.N. Lachinov2, V.V. Shaposhnikova3,
S.N. Salazkin3, V.P. Kazakov1
1 - Institute of Organic Chemistry URC RAS, Ufa, Russia
2 - Institute of Physics of Molecules and Crystals URC RAS, Ufa, Russia
3 - Institute of Elementoorganic Chemistry RAS, Moscow, Russia
lachinov@anrb.ru
Influence of the copolymer structure on the electroluminescence (EL) parameters has been
investigated in this study. Copolymers, polyaryleneetherketones were tested. This copolymers
are non-conjugated.
However, if these copolymers have a phtalyde or dimethyl groups, these copolymers are able to
conduct high current in film structure. That’s why the electric switching effect is observed in
these polymers. The series of six polymers were studied. Polymers difference by content of the
phtalyde and dimethyl groups (from 1% to 50%).
EL measurements were carried out at the AL/polymer/ITO multilayer structure (ITO is a mixture
of indium and tin oxides). The following parameters had been measured: the current-voltage
characteristics, the photoluminescence spectrums, the excitation spectrum and the applied
voltage dependence of the EL quantum efficiency. In state of comparison of the obtained results
and previously published data studies with the polydiphenylenephtalide had been conducted.
Dependences of the quantum efficiency on the percentage of the phtalide or phluorenon groups
in the polymer chain are shown in fig. 1.
Q
u
a
n
t
u
m
Q
u
a
n
t
u
m
e
f
f
i
c
i
e
n
c
y
e
f
f
i
c
i
e
n
c
y
Fig. 1. Dependence of the quantum efficiency on the percentage of the phtalide or dimethyl
groups in the copolymer polyaryleneetherketones. Excitation of the EL is at the direct (left) and
reverse (right) polarity.
The following features had been established during the investigation:
1. EL is observed in all series of the samples.
2. The quantum efficiently strongly depends on the chemical structure of the polymer, on
the phtalide group percentage particularly.
3. EL is observed with both polarity of the applied voltage.
4. Change of the EL spectrum is observed at the change of the polarity.
210
PHOTOPHYSICAL PROPERTIES OF HIGHLY LUMINESCENT
PLATINUM 1,3,5-TRIAZAPENTADIENE COMPLEXES IN FLUID,
ADSORBED AND SOLID STATE
P.V. Gushchin1, N. Chakrova1, S.V. Litke1, G.N. Lyalin1, V.G. Maslov2
SPbSU
2 - SPbSU ITMO
glialin@yandex.ru
Luminescent square-planar platinum(II) complexes have attracted a great attention due to their
intriguing useful photophysical and photochemical properties. In this paper we report the results
of study of two the most highly luminescent Pt-comlexes of the new family Platinum 1,3,5Triazapentadiene complexes, the first synthesized in the Institute of Chemistry of SPbU1,2.
[Pt{NH=C(Ph)-NC(Ph)=NPh}2] (1)
[Pt{NH=C(Ph)NC(NHPh)=NPh}2] (2)
The results of measurements of absorption, luminescence, excitatation of luminescence,
lifetime of luminescence and luminescence quantum yield of complexes in solution, adsorbed
on SiO2, in polystyrene matrix and in the solid state are summarized in the table.
Absorption
⋋/nm
(ε/M-1cm-1)
Excitation RT
⋋/nm
Emission RT
⋋em/nm,
ΦL
Degassed
τ/µs,
Degassed
τ/µs,
Air-satureted
complex
1
2
1
2
1
2
1
2
241
256
293
415
298
330
315
380
400
293
320
415
315
380
400
535
540
298
330
427
450
335
380
426
526
555
491
523
0.4
500
536
0.74
527
0.3
1
2
1
2
matrix
CH2Cl2
Polylst.
350
430
465
Polycrst.
SiO2
318
396
424
344
390
417
534
(RT)
548
(77K
0,004
0.01
0.007
1.85
3.4
(RT)
3.65
(77K)
2.62
1.83
0.81
(RT)
2.77
(77K)
0.76
1.92
(RT)
0.4
1,6
(RT)
0.4
1.5
(RT)
0.7
2.0
(RT)
4.2
(77K)
0.76
1.92
(RT)
1.91
(77K)
0.4
1.6
(RT)
3.05
(77K)
To gain more insight into the above photophysical behavior, the electronic transition properties
calculations of complexes were performed using time dependent density functional theory
method (TDDFT) in the base of SBKJC.
We studied also the luminescent properties of the complexes in different solvents such as
dichloromethane, dibromomethane, nitromethane, acetonitrile, dimethyl sulfoxide. It was shown
the typical quenching processes associated with e.g. solvent collision and formation contact
complex (CT) between excited state of complex during it`s life time and solvent.
1. P. V. Gushchin, M. R. Tyan, N. A. Bokach, M. D. Revenco, M.Haukka, M-J. Wang, C-H. Lai,
P-T. Chou, and V. Yu. Kukushkin. Inorg. Chem., 2008, 47 (24), 11487-11500.
2. .H.Sarova, N.A.Bokach, A.A.Fedorov, M.N.Berberan-Santos, V.Y.Kukushkin, M.Haukka,
J.R.Frausto da Silva, A.J.Pombeiro. Dalton Trans., 2006,3798-3805.
211
INTRAMOLECULAR EXCITATION ENERGY TRANSFER
IN Zn OCTACARBOXYPHTHALOCYANINE TETRACONJUGATE
WITH RHODAMINE C
D.A. Makarov, L.P. Savvina, L.I. Solovyova, L.E. Marinina,
N.A. Kuznetsova, O.L. Kaliya, E.A. Lukyanets
Institute of Organic Intermediates and Dyes, Moscow, Russia
jerrik@rol.ru
Tetraconjugate of octacarboxysubstituted zinc phthalocyanine (OCZnPc) with Rhodamine C
(RhC) (conjugate) has been synthesized. The absorption spectrum of conjugate in visible region
has rhodamine and phthalocyanine bands (in DMSO at 565 nm and 703 nm accordingly).
Intramolecular excitation energy transfer in conjugate from rhodamine to phthalocyanine part
has been investigated by fluorescence and singlet oxygen generation studies.
The energy transfer in conjugate in DMSO results in quenching of the donor (rhodamine)
fluorescence and appearance of the acceptor (phthalocyanine) fluorescence at excitation of the
rhodamine part.
RN
O
O
C
C
O C
NR
C O
O
N
N
N
CH2CH2O C
N
Zn
N
N
N
C O
O C
RN
R=
N
C
C
O
O
H5C2 N
H5C2
N
O
Cl
C2 H 5
C 2H 5
NR
The singlet oxygen quantum yields (Φ∆) studies in DMSO have confirmed intramolecular
excited energy transfer from rhodamine to phthalocyanine part in this molecular system. Thus,
RhC alone has negligible ability to sensitize 1O2 formation (the quantum yield Φ∆ for RhC is <
0.01). However, under excitation of RhC, conjugated with OCZnPc, formation of 1O2 with rather
high quantum yield of 0.25 was observed. This finding clearly indicates energy transfer from
rhodamine residues to 1O2 generating phthalocyanine part of conjugate. It can be noticed that Φ∆
values for conjugate both under selective excitation of rhodamine or phthalocyanine
chromophores are equal to 0.25, that is substantially, about three times lower than Φ∆=0.70 for
unbounded OCZnPc.
It was found that the fluorescence and singlet oxygen quantum yields for conjugate are smaller
than for unbounded dyes. This finding suggests appearance in conjugate of competitive chargetransfer-mediated process of excitation energy dissipation.
212
NONLINEAR OPTICAL PROPERTIES OF FULLERENE-DOPED
ORGANIC STRUCTURES
A.I. Plekhanov1, N.V. Kamanina2, A.E. Simanchuk1
1 – Institute of Automation and Electrometry SB RAS, Novosibirsk, Russia
2 – S.I. Vavilov State Optical Institute, St.Petersburg, Russia
fractal@iae.nsk.su
Fullerene-doped conjugated organic structures offer a special interest among a wide
variety of nanostructures. Such structures possess a high nonlinear optical response. In this work
the number of film-like samples was investigated: both the pure fullerene samples and the
fullerene-doped π-conjugated organic structures [1,2].
The thickness of the films varied from 0.5 to 2 mkm. We have studied the nonlinear
optical response of thin films by z-scan method and four-photon mixture at nanosecond and
picoseconds excitation at the wavelength of 532 nm. The obtained data are compared with the
nonlinear optical properties of other materials known from the literature [1-9].
From the comparison follows that the nonlinear optical parameters of fulleren-doped
polymer nanostructures are larger than those obtained for traditional nonlinear systems that
permit to apply these materials as effective holographic recording element, spatial light
modulator, switchers, nonlinear absorber in the visible and in the near-infrared spectral ranges.
Moreover, the data testify that nonlinear characteristics of the materials studied are close to the
Si-based structures that provoke the organics structures with nanoobjects to be used in organic
solar energy technique.
[1] Kamanina, N. V. Optics and Spectroscopy, 90, 867 (2001).
[2] Kamanina, N. V. Synthetic Metals, 139, 547 (2003).
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[4] Kaizar, F., Taliani, C., Muccini, M., Zamboni, R., Rossini, S., Danieli, R. Proceed. SPIE,
2284, 58 (1994).
[5] Li, J., Feng, J., Sun, J. J. Chem.Phys., 203, 560 (1993).
[6] Krätschmer, W., Lamb, L. D., Fostiropoulos, K., Huffman, D. R. Nature, 347, 354 (1990).
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[8] Ganeev, R. A., Ryasnyansky, A. I., Kodirov, M. K., Usmanov, T. Opt. Commun., 185, 473
(2000).
[9] Kamanina, N. V., Sheka, E. F. Opt. Spectrosc., 96, 599 (2004).
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FTIR STUDY OF OZONOLYSIS AND PHOTOOXIDATION
OF ADSORBED CHLOROETHENES
A.A. Tsyganenko, N.V. Zakharov, N.M. Tsyganenko
V.A. Fock Institute of Physics, St.Petersburg State University, Russia
tsyg@photonics.phys.spbu.ru
Surface chemistry of halogenated hydrocarbons attracts much attention in the recent years due to
their role in stratospheric ozone destruction. The aim of this work was to study surface reactions
of chloroethenes with ozone at 77-293 K on two different oxides, which could be considered as
model aerosols: relatively inert SiO2 and catalytically active TiO2. To see the effect of adsorbed
H2O, experiments with TiO2 were carried out at different stages of surface dehydration.
FTIR spectra of all chlorinated ethenes (C2H3Cl, trans, cis and gem isomers of C2H2Cl2, C2HCl3
and C2Cl4) adsorbed on TiO2 and SiO2 reveal only molecular adsorption at temperatures below
ambient. For monochloroethene, ozone admission, besides the bands of adsorbed ozone1,2,
results in the appearance of new bands of products already at 77 K in the spectra of the studied
samples. Adsorbed di-, three- and tetrachloroethene are less reactive towards ozone and either
react at higher temperature (cis and trans-dichloroethenes) or do not display formation of
products at all (C2HCl3 and C2Cl4 on silica). TiO2 exhibit higher activity towards ozonolysis of
chloroethenes. For all the adsorbates weak bands of products start to grow in the spectra of
titania already at 77 K. Preliminary water adsorption decreases the activity of TiO2, delaying the
starting temperature of reaction up to 100- 140 K. Among the first products of ozonolysis,
formaldehyde (bands at about 1720 and 1500 cm-1), phosgene (1805 cm-1) and formylchloryde
HClCO were identified, as well as the bands assignable to primary or secondary ozonides, while
at the final stage water, CO2 and surface carboxylate-like species appear. The mechanism of
reaction is consistent with Criegee’s scheme, as in the case of ozone interaction with ethene
adsorbed on silica3.
Degradation of chlorinated hydrocarbons in atmosphere can be stimulated by UV irradiation. To
reproduce this effect we have studied the changes in the spectra of gem-dichloroethene adsorbed
on TiO2 in the presence of oxygen under irradiation by undecomposed light of mercury lamp in
the quarts tube at 300 K. Decrease of the bands of adsorbed molecules as well as the appearance
of new bands of photoproducts testify for the dichloroethene photooxidation, although the final
spectrum was different from that after ozonolysis. No photooxidation was detected on silica, but
irradiation at 77 K in the presence of ozone leads to oxidation of dichloroethenes even on inert
surfaces, such as silica or disperse ice4, apparently, due to photoactivation of ozone molecules by
UV light.
Acknowledgement. The authors acknowledge with thanks the support of this work by grants
INTAS 03-51-5698, RFFI 06-03-32836a and RFFI 06-05-64646a.
References:
1. Bulanin K.M., Alexeev A.V., Bystrov D.S., Lavalley J.-C., Tsyganenko A.A. J. Phys. Chem., 98
(1994), 5100.
2. Bulanin K.M., Lavalley J.-C., Tsyganenko A.A. J. Phys.Chem. 99 (1995), 10294.
3. Manoilova O.V., Lavalley J.-C., Tsyganenko N.M., Tsyganenko A.A. Langmuir, 14 (1998), 5813.
4. A.V. Rudakova, V.N. Sekushin, I.L. Marinov, A.A. Tsyganenko. Molecules in Space and Laboratory.
Proc. Int. Conf. Paris, France, 2007.
214