CODECS 2013 Workshop
San Lorenzo de el Escorial, Madrid, 18th –22nd April, 2013
Theoretical analysis of electronic transitions in charge-transfer
complexes based on TCNE and TCNQ acceptors
Šimon Budzáka, Ondrej Kyseľa, Miroslav Medveďa, Pavel Machb, Tímea Kevelyováa,
Lucia Verešováa, Leif A. Erikssonc
a
Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, SK97400 Banská Bystrica, Slovak Republic
b
Department of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics and
Informatics, Comenius University, Mlynská dolina CH1, SK-84215 Bratislava, Slovak Republic
c
Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, SE 405
30 Göteborg, Sweden
Photophysical and photochemical properties of charge-transfer (CT), or electron donoracceptor (EDA), complexes have been of interest for a long time mainly due to their wide
spectrum of applications ranging from chemistry, material science, and medicine to biology.
In our work we analyze CT absorption and emission spectra of various inter- as well as intramolecular EDA systems containing strong electron-acceptor moieties such as TCNE and TCNQ.
In order to systematically study the donor effects, a complete series of methylated benzenes
(NMB) have been chosen, since of their donor strength can be controlled by the extent of
methylation [1]. Moreover, experimental data on absorption and fluorescence spectra both in gas
phase and in polar solvents are available for these systems enabling straightforward comparison
with theoretical results. The solvent effects on the CT transitions are studied by using efficient
PCM model as well as modern MD approaches.
In order to control the efficiency of the electron transfer on the acceptor side, the acceptor
strengths of TCNE and TCNQ are compared to those exhibited by halogenated quinones
representing another important group of electron acceptors.
Finally, preliminary results on the electronic transitions in intramolecular CT systems derived
from TCNQ as an acceptor and TTF as a donor moiety linked by either fully saturated (σ-) chains
or π-conjugated linkers will be presented.
Acknowledgments
This work has been supported by the Slovak Research and Development Agency (project No.
APVV-0059-10). The COST-CMTS Action CM1002 ‘‘COnvergent Distributed Environment for
Computational Spectroscopy (CODECS)’’ is also acknowledged.
References
1. P. Mach, Š. Budzák, M. Medveď, O. Kyseľ, Theor. Chem. Acc., 131, 1268 (2012).