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On the Nature of Ni…Ni Interaction in Model Dimeric Ni Complex
Radosław Kamiński,a* Beata Herbaczyńska,b Monika Srebro,c Antoni Pietrzykowski,b
Artur Michalak,c Lucjan B. Jerzykiewicz,d Krzysztof Woźniaka*
a
Department of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warszawa, Poland
Department of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664
Warszawa, Poland
c
Department of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
d
Department of Chemistry, Wrocław University, Joliot-Curie 14, 50-383 Wrocław, Poland
b
*
Corresponding authors: Radosław Kamiński (rkaminski@chem.uw.edu.pl),
Krzysztof Woźniak (kwozniak@chem.uw.edu.pl)
Keywords: nickel complexes, charge density studies, metal-metal bonding, DFT
calculations, orbital analysis
Abstract: A new dinuclear complex (NiC5H4SiMe2CHCH2)2 (2) was prepared by reacting
nickelocene derivative [(C5H4SiMe2CH=CH2)2Ni] (1) with methyllithium (MeLi). Good
quality crystals were subjected to a high-resolution X-ray measurement. Subsequent multipole
refinement yielded accurate description of electron density distribution. Detailed inspection of
experimental electron density in Ni…Ni contact revealed that the nickel atoms are bonded and
significant deformation of the metal valence shell is related to different populations of the dorbitals. The existence of the Ni…Ni bond path explains the lack of unpaired electrons in the
complex due to a possible exchange channel.
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1. Synthesis of starting materials
1.1. General Information. All reactions and manipulations were carried out under an
atmosphere of dry argon. Solvents were dried with potassium and distilled prior to use.
Chloro(dimethyl)vinylsilane (Sigma-Aldrich) was distilled under an argon atmosphere prior
to use. Solutions of n-butyllithium in heptane and of methyllithium in diethylether (SigmaAldrich) were used as purchased. Cyclopentadiene was prepared by distillation of
dicyclopentadiene (Fluka) (through retro-Diels-Alder reaction). NiBr2·2DME was prepared
by the reaction of nickel powder with bromine in the presence of dimethyl ether (DME). 1H
NMR (400 MHz) spectra were recorded on a Mercury-400BB spectrometer in benzene-d6 at
ambient temperature. Mass spectra (EI, 70 eV) were recorded on an AMD-604 mass
spectrometer. Reactions are presented in Scheme 1S.
H
BuLi
_
Li
H
Me
Cl
+
Me
Me
Me
Si
1) BuLi
2) NiBr2 . 2 DME
1
Si
Scheme 1S. Synthesis of the compound 1.
1.2. One-pot synthesis of 1,1’-bis[dimethyl(vinyl)silyl]nickelocene (1). A solution of
10.85 cm3 BuLi (2.3 M in heptane, 25.0 mmol) was added within 1 min with a syringe to a
solution of 2.05 cm3 (25.0 mmol) of freshly distilled cyclopentadiene in 60 cm3 THF at 0°C.
After stirring for 1 h at room temperature, the solution of cyclopentadienyllithium was cooled
to 0°C and 3.45 cm3 (25.0 mmol) of chloro(dimethyl)vinylsilane was added within 1 min. The
orange-yellow solution of dimethyl(vinyl)silylcyclopentadiene was stirred for 1 h at room
temperature. The reaction mixture was then cooled again to 0°C and the second portion of
BuLi solution (10.85 cm3, 25.0 mmol) was added drop by drop. After 1 h at room
temperature, the reaction mixture was cooled to 0°C and transferred slowly (within 10 min) to
a suspension of 5.00 g (12.5 mmol) NiBr2·2DME in 40 cm3 THF. The color of the solution
changed immediately to green. After stirring for 4 h at room temperature the solvent was
removed under reduced pressure. Residue was dissolved in 100 cm3 diethyl ether and 60 cm3
of water was added. After stirring the mixture for 30 min, the organic layer was separated,
solvents were evaporated and the residue was dried under reduced pressure. 50 cm3 of hexane
was added to the green oil and the solution was filtered through a bed of Celite. Hexane was
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distilled off and the residue was dried under reduced pressure. 3.91 g (10.9 mmol) of 1,1’bis[dimethyl(vinyl)silyl]nickelocene was obtained as a green oil (yield: 87%). M.p. = ca. –
65°C. 1H NMR (benzene-d6, 400.1 MHz): from –200 to 200 ppm no signals. EI-MS m/z: 356
(M+, 70%), 300 (C18H26Si2 + 2H, 12%), 298 (C18H26Si2, 15%), 262 (10%), 244 (10%), 207
(C9H13SiNi, 12%). EI-HRMS: (C18H26Si258Ni) calculated 356.09265, found 356.09354.
1.3. Synthesis of bis[dimethyl(vinyl)silylcyclopentadienylnickel] (2). The solution of
1.00 g (2.8 mmol) of 1 in 20 cm3 of THF and 40 cm3 of diethyl ether was cooled to –75°C.
3.10 cm3 of methyllithium (1.2 M in diethyl ether, 3.7 mmol) was then added drop by drop
within 3 min. After stirring for 1 h the solution was slowly warmed up to room temperature
and stirred for additional 3 h. Next, 50 cm3 of water was added and the mixture was stirred for
20 min. the organic layer was separated, solvents were evaporated and the residue was dried
under reduced pressure. The obtained green solid was re-dissolved in 20 cm3 of heptane and
filtered through a bed of Celite. Dark green crystals of 2 were obtained from this solution at –
30°C (0.48 g, 1.1 mmol, yield 82 %). 1H NMR (benzene-d6, 400 MHz) δ / ppm: 5.64 (s, 1H,
C5H4), 5.51 (s, 1H, C5H4), 5.22 (s, 1H, C5H4), 5.04 (d, JH–H = 15.7 Hz, 1H, trans-CH=CH2),
3.52 (s, 1H, C5H4), 3.44 (d, JH–H = 11.5 Hz, 1H, cis-CH=CH2), 2.46 (dd, JH-H =15.7 and 11.5
Hz, 1H, Si–CH=CH2), 0.78 (s, 3H, Si–CH3), 0.28 (s, 3H, Si–CH3).
13
C NMR (benzene-d6,
100.1 MHz) δ / ppm: 93.97, 93.82, 92.55, 91.05, 49.29, 45.59, 2.08, –1.51. EI-MS m/z: 414
(M+, 5%), 356 (M+–Ni, 100%), 300 (C18H26Si2 + 2H, 18%), 298 (C18H26Si2, 16%), 262
(12%), 244 (12%), 207 (C9H13SiNi, 10%). Crystals suitable for high-resolution X-ray
diffraction experiment were obtained by slow re-crystallization from heptane at 0°C.
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2. X-ray data collection and refinement
2.1. General. A single crystal high-resolution X-ray data collection for 2 was performed
on a Bruker Kappa APEX II Ultra diffractometer equipped with a TXS rotating anode (MoKα
radiation, λ = 0.71073 Å), multi-layer optics and an Oxford Cryosystems nitrogen gas-flow
apparatus. A single crystal of suitable size was attached to a cactus spine using Paratone N
oil, mounted on a goniometer head 50 (first 12 runs – low angle data) and 40 mm (high angle
data) from the APEX II CCD camera and maintained at a temperature of 90 K. Details of the
data collection are given in Table 1S. The data collection strategy was optimized and
monitored using the appropriate algorithms implemented by the APEX2 program.[1] Only the
ω scans were taken into account, using 0.3° intervals with a counting time of 10 s and 90 s for
low and high angle data respectively, resulting in a total of 8832 frames. Determination of the
unit cell parameters and integration of the raw images was performed with the APEX2 suite of
programs (integration was done by SAINT[1]). The data set was corrected for Lorentz and
polarization effects. The multi-scan absorption correction, scaling and merging of reflections
were done with SORTAV.[2]
2.2. IAM refinement. Structure was solved by direct methods using SHELXS-97[3] and
refined using SHELXL-97[3] using the IAM approximation. The refinement was based on F2
for all reflections except those with very negative F2. Weighted R factors (wR) and all
goodness-of-fit (GooF) values are based on F2. Conventional R factors are based on F with F
set to zero for negative F2. The Fo2 > 2σ(Fo2) criterion was used only for calculating R factors
and is not relevant to the choice of reflections for the refinement. The R factors based on F2
are about twice as large as those based on F. Scattering factors were taken from the
International Tables for Crystallography.[4] All non-hydrogen atoms were refined
anisotropically. Hydrogen atoms of C–H bonds were placed in idealized positions(all these
hydrogen atoms were visible on difference density maps). The lattice parameters, including
the final R indices obtained by spherical refinement, are presented in Table 1S.
2.3. Multipole refinement. Multipole refinement of 2 was performed with the XDLSM
module of the XD program suite,[5] using the Hansen-Coppens formalism.[6] In this formalism,
the total atomic electron density (of the k-th atom) is a sum of three components:
lmax
l
ρk (r ) = ρck (r ) + Pvk κ ρvk (κ k r ) +   Plmk κ '3lk Rlk (κ 'lk r )d lmk (r / r )
3
k
l =0 m= − l
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where ρc and ρk are spherical core and valence densities, respectively. The third term contains
the sum of the angular functions (dlm) that take into account aspherical deformations. The
angular functions dlm are real spherical harmonic functions, which are normalized for the
electron density. The coefficients Pv and Plm are multipole populations for the valence and
deformation density multipoles, respectively. κ and κ’ are scaling parameters which control
the expansion or contraction of the valence and deformation densities, respectively. In the
Hansen-Coppens formalism, Pv, Plm, κ and κ’ are refinable parameters together with the
atomic coordinates and thermal motion coefficients. Here the P00 parameter was not refined as
it is highly correlated with Pv.
The least-squares multipole refinement was based on F2, with only those reflections with
I > 3σ(I). Atomic coordinates x, y, and z and anisotropic displacement parameters (Uij) for
each atom were taken from the spherical refinement stage and freely refined. Each atom was
assigned core and spherical-valence scattering factors derived from atomic Volkov and
Macchi wave functions[5] A single-ζ Slater-type radial function multiplied by densitynormalized spherical harmonics was used for describing the valence deformation terms. The
multipole expansion was truncated at the hexadecapole (lmax = 4) and quadrupole (lmax = 2)
levels for all non-hydrogen and hydrogen atoms, respectively. The valence-deformation radial
fits were described by the use of their expansion-contraction parameters κ and κ’. The κ
values were refined for non-hydrogen atoms and constrained to 1.20 for hydrogen atoms.
Identical values of the κ’ parameter was used for all l > 0 multipoles for all other nonhydrogen atoms and kept unrefined at values of 1.20 for hydrogen atoms. No symmetry
constraints were applied. The parameters refined at each stage of the refinement strategy were
as follows: (1) only the scale factor (which was also refined in other stages of the procedure);
(2) the coordinates together with thermal parameters for non-hydrogen atoms were refined
against the high-angle data (sinθ/λ > 0.8 Å–1); (3) coordinates together with isotropic thermal
parameters for hydrogen atoms against the low-angle data (sinθ/λ < 0.6 Å–1); (5) the hydrogen
atom positions were shifted along the bond directions found to the standardized average
neutron values (1.083 Å, 1.059 Å and 1.077 Å for CAr–H, CMe–H and C=C–H bond distances,
respectively[7]; recent paper of Allen and Bruno[8] corrects some of those values using updated
database with 495 968 entries, however, we did not observed significant differences, and thus
the original model is presented here) and the isotropic thermal parameters for the nonhydrogen atoms at the high-angle data (sinθ/λ > 0.8 Å–1); (6) estimation of anisotropic thermal
parameters for hydrogen atoms was accomplished using the SHADE2 server[9] (see Figure 5S;
such a procedure have been recently shown to be the best approach, at least within the
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Hansen-Coppens approximation, for hydrogen atoms treatment[10]); (7) κ parameters for the
non-hydrogen atoms; (8) multipole parameters refined in a stepwise manner; (9) coordinates
and thermal parameters together with all multipole populations; (10) κ and κ’ parameters; (11)
coordinates and thermal parameters together with all multipole populations. Proper
deconvolution of thermal motion from the density features was tested by using the Hirshfeld
rigid-bond test.[11] The differences of mean-squares displacement amplitudes (DMSDA) were
higher than the 0.001 Å2 limit for the Ni–C bonds (this was analyzed previously in the
literature for Fe–Cp[12] and this phenomenon is due to the liability of Cp rings). For the rest of
the bonds the highest DMSDA values are oberved for Si–CMe bonds (probably because of the
mass difference).
According to the above general refinement strategy, several models with different
scattering factors were tested but there were no significant changes in the final electron
density results obtained. The maximum and minimum of residual density were equal to
+0.331 e·Å–3 and –0.264 e·Å–3, respectively. The residual density maps show some deviations
near the nickel atoms (see Figures 1S). The presence of anharmonic vibrations was excluded,
as their refinement did not improve the model in any way. All R-factors and other parameters
characterizing the refinement, residual density maps, static deformation and laplacian maps
are presented in Table 1S and in Figures 1S-5S.
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Table 1S. Crystal and refinement data for compound 2.
Formula
Molecular mass
Measurement temperature (T)
Crystal system
Space group
Unit cell parameters:
a
b
c
α
β
γ
Volume (V)
Z
Calculated density
F(000)
Crystal size
θ range for data collection
Absorption coefficient (μabs)
(sinθ/λ)max
Index ranges
C18H26Ni2Si2
415.99 a.u.
90(2) K
monoclinic
C2/c
No. of reflections collected / unique
Completeness
Rint
Absorption correction
18.1708(7) Å
6.5265(2) Å
17.4683(7) Å
90°
116.7710(10)°
90°
1849.55(12) Å3
4
1.494 g·cm–3
872
0.102 × 0.154 × 0.311 mm3
2.51 – 50.70°
2.168 mm–1
1.09 Å–1
–39 < h < 39
–14 < k < 14
–37 < l < 37
89835 / 9930
> 99%
3.28 %
multi-scan
IAM refinement
No. reflections / restrains / parameters
R(F) / wR(F2) [for I > 2σ(I)]
R(F) / wR(F2) [for all data]
GooF
Largest residual density peak and hole
9930 / 0 / 100
2.55% / 6.85%
2.99% / 7.12%
1.114
+1.782 e·Å–3 / –0.634 e·Å–3
Multipole refinement
No. of reflections [for I > 3σ(I)] / parameters
R(F] / wR(F2) [for I > 3σ(I)]
R(F2] / wR(F2) [for I > 3σ(I)]
R(F] / R(F2) [for all data]
GooF [for I > 3σ(I)]
Largest residual density peak and hole
8383 / 492 = 17.04
1.23% / 1.83%
1.73% / 3.43%
1.76% / 1.78%
1.072
+0.331 e·Å–3 / –0.264 e·Å–3
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3. Computational details
3.1. ADF calculations. All the results were obtained from the DFT calculations based on
the Becke-Perdew exchange-correlation functional,[13] using the Amsterdam Density
Functional (ADF) program, version 2009.01.[14] A standard double-ζ STO basis with one set
of polarization functions was used for main-group elements, H, C and Si, while a standard
triple-ζ STO basis set was employed for a transition metal, Ni. The 1s electrons of C, as well
as the 1s-2p electrons of Si and Ni were treated as frozen core. Auxiliary s, p, d, f and g STO
functions, centered on all nuclei, were used to fit the electron density and obtain an accurate
Coulomb potential in each SCF cycle. Relativistic effects were considered using the firstorder scalar relativistic correction.[15]
3.2. Energy decomposition scheme. In the Ziegler-Rauk bond energy decomposition
analysis[16] total interaction energy of distorted fragments in a molecule is divided into
following components:
ΔE tot = ΔE steric + ΔE orb = (ΔE elstat + ΔE Pauli ) + ΔE orb
The first contribution, ΔEsteric , corresponds to the steric interaction between the fragment
considered. It comprises two terms, namely (i) the classical electrostatic interaction between
the promoted fragments, ΔEelstat , and (ii) the Pauli repulsion between the occupied orbitals on
the two fragments, ΔEPauli . The second component is the orbital interaction term, ΔEorb ,
representing the interactions between the occupied molecular orbitals on one fragment with
the unoccupied molecular orbitals of the other fragment as well as mixing of occupied and
virtual orbitals within the same fragment (intra-fragment polarization). This latter term may
be directly linked to the electronic bonding effect coming from the formation of a chemical
bond.
Natural Orbitals for Chemical Valence (NOCV) are obtained by diagonalization of the
deformational density matrix.[17] They can be grouped in pairs (ϕ −k , ϕ k ) characterized by the
eigenvalues of the opposite sign and the same absolute value, vk. Thus, the NOCV pairs allow
for a decomposition of the differential Δρ, into NOCV contributions, Δρk:[17]
n/2
[
]
n/2
Δρ(r ) =  ν k − ϕ −2k (r ) + ϕ k2 (r ) =  Δρ k (r )
k =1
k =1
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The picture of the bonding obtained from the deformational density NOCV contributions, is
further enriched by providing the energetic estimations, ΔEorb (k ) , for each Δρk within the
ETS-NOCV method.[17-18] In such a combined scheme the orbital interaction term is expressed
in terms of NOCVs eigenvalues as:
n/2
n/2
k =1
k =1
[
TS
ΔE orb =  ΔE orb (k ) =  ν k − F−TS
k , − k + Fk , k
]
where Fi ,iTS are the diagonal Kohn-Sham matrix elements defined over NOCV with respect to
the transition state (TS) density at the midpoint between density of the molecule and the sum
of fragment densities. This term gives the energetic measure of Δρk that may be related to the
importance of a particular electron flow channel contributing to the bonding between
fragments considered.
3.3. Topological analysis. Bader’s Quantum Theory of Atoms In Molecules[19] (QTAIM)
was applied to perform topological analysis of experimental and theoretical electron density
distributions.. In the framework of this approach Critical Points (CPs) together with the Bond
Paths (BPs) were found as well as valence shell charge concentrations (VSCCs). In order to
determine the nature and relative strength of the bonds, electron density and its Laplacian
were evaluated at the BCPs. Atomic charges, dipoles and sources were calculated by
integrating the respective quantities within the corresponding atomic basins. For theoretically
obtained structures all analyses were carried out with DGRID program,[20] whereas for
experimental data topological analyses were done with XDPROP and TOPXD modules from
the XD package.
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4. Supporting maps, plots and figures
(a)
(b)
( c)
Figure 1S. Residual density maps for 2 after multipole refinement: (a) Ni(1)Ni(1)#C(3)#
plane; (b) Ni(1)C(10)#C(11)# plane; (c) C(3)C(5)C(6) plane (# – 2-fold symmetry
transformation present in C2/c space group). Contours at ±0.05·n e·Å–3 (n = 1, 2, …). Color
coding: blue solid lines – positive values, red dashed lines – negative values, black dotted line
– zero contour.
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(a)
(b)
Figure 2S. Static deformation density maps for 2 after multipole refinement: (a)
Ni(1)C(10)#C(11)# plane (# – 2-fold symmetry transformation, contours at ±0.3·n e·Å–3, n =
1, 2, …); (b) C(3)C(5)C(6) plane (contours at ±0.1·n e·Å–3, n = 1, 2, …) Color coding: blue
solid lines – positive values, red dashed lines – negative values, black dotted line – zero
contour.
Figure 3S. Normal probability plot for 2 after final multipole refinement.
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Figure 4S. Scale plot for 2 after final multipole refinement.
Figure 5S. SHADE-estimated ADPs for hydrogen atoms (only the asymmetric part is shown).
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(a)
(b)
Figure 6S. Isosurface representations of negative electron density Laplacian distributions in
the vicinity of nickel atoms: (a) theoretical data for model system (1566 e·Å–5); (b)
experimental data for complex 2 (1807 e·Å–5).
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Figure 7S. Local source function profiles along Ni…Ni bond. The reference point is taken as
the BCP of the nickel…nickel interaction: (a) IAM (red curve) and (b) multipole model (blue
curve). The respective integrated source function contributions for the Ni atom are equal to
about 0.014 e·Å–3 and 0.020 e·Å–3 for the IAM and multipole model, respectively. The
contribution for IAM is clearly much smaller compared with the multipole model (as it could
be concluded from the local source profiles). This might suggest a weaker charge depletion
from the 3rd atomic shell of the Ni atom (i.e. from the region around at 0.45 Å from the
nucleus), as it is anticipated in the IAM, and may explain rather small positive charge on the
metal atom (ca. +0.5 e). Also it suggests that the atomic core is less flexible (in terms of
deformations) for the NiI complexes in comparison with NiII compounds. The detailed
analysis is beyond the scope of this paper and will be published elsewhere.
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5. Supporting tables
Table 2S. Maxima and minima of residual density (RMS = 0.047 e·Å–3).
Highest
peaks
1
2
3
4
5
6
7
8
9
10
Deepest
holes
1
2
3
4
5
6
7
8
9
10
Height / e·Å–3
Remarks
0.33
0.30
0.29
0.29
0.20
0.20
0.19
0.18
0.18
0.18
Random position
0.74 Å from Ni(1)
Random position
0.74 Å from Ni(1)
0.31 Å from Si(2)
Random position
Random position
1.03 Å from Ni(1)
Random position
Random position
Height / e·Å–3
Remarks
–0.27
–0.22
–0.22
–0.20
–0.19
–0.18
–0.18
–0.17
–0.17
–0.17
0.73 Å from Ni(1)
0.71 Å from Ni(1)
1.04 Å from Si(2)
Random position
0.72 Å from Si(2)
0.39 Å from C(10)
Random position
Random position
0.45 Å from C(8)
Random position
Table 3S. Selected geometrical and topological parameters in BCPs for 2 (a) and optimized
model system (b) (d – bond length, ρ – electron density, # – 2-fold symmetry axis
transformation).
(a)
Bond
Ni(1)–Ni(1)#
Ni(1)–C(3)
Ni(1)–C(4)
Ni(1)–C(5)
Ni(1)–C(6)
Ni(1)–C(7)
Ni(1)–C(10)#
Ni(1)–C(11)#
Si(2)–C(3)
Si(2)–C(8)
Si(2)–C(9)
Si(2)–C(10)
C(3)–C(4)
C(4)–C(5)
C(5)–C(6)
C(6)–C(7)
C(7)–C(3)
C(10)–C(11)
C(4)–H (4A)
C(5)–H (5A)
C(6)–H (6A)
(b)
d/Å
ρ / e·Å–3
2.5152(1)
2.0975(3)
2.1561(3)
2.1655(4)
2.1575(4)
2.0933(4)
2.0048(3)
1.9888(4)
1.8637(3)
1.8733(4)
1.8646(4)
1.8604(3)
1.4282(5)
1.4221(6)
1.4291(6)
1.4125(5)
1.4556(5)
1.4103(5)
1.083
1.083
1.083
0.235(1)
0.51(1)
–
0.48(1)
0.47(1)
–
0.66(2)
0.61(2)
0.87(2)
0.85(2)
0.86(2)
1.00(3)
1.96(3)
2.03(4)
2.04(3)
2.06(3)
1.84(3)
1.97(3)
1.91(7)
1.86(7)
1.86(7)
2
∇ρ
–5
/ e·Å
1.746(1)
5.40(2)
–
5.38(2)
5.43(2)
–
6.29(3)
6.54(4)
0.64(7)
0.29(7)
–2.62(7)
–2.12(8)
–16.1(1)
–14.1(1)
–18.1(1)
–15.4(1)
–12.8(1)
–12.9(1)
–19.6(3)
–17.1(3)
–18.4(3)
d/Å
ρ / e·Å–3
2.496
2.079
2.147
2.193
2.206
2.163
1.995
1.991
–
–
–
–
1.435
1.417
1.435
1.412
1.438
1.407
1.086
1.088
1.088
0.297
0.532
–
–
0.420
–
0.655
0.659
–
–
–
–
1.881
1.950
1.883
1.970
1.866
1.960
1.848
1.848
1.850
∇2ρ
/ e·Å–5
1.227
5.092
–
–
5.085
–
5.186
5.155
–
–
–
–
-15.141
-16.334
-15.329
-16.647
-14.973
-16.414
-22.462
-22.544
-22.578
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C(7)–H (7A)
C(8)–H (8A)
C(8)–H (8B)
C(8)–H (8C)
C(9)–H (9A)
C(9)–H (9B)
C(9)–H (9C)
C(10)–H (10A)
C(11)–H (11A)
C(11)–H (11B)
C(3)–H (3A)
C(10)–H(10B)
1.083
1.059
1.059
1.059
1.059
1.059
1.059
1.077
1.077
1.077
–
–
1.84(7)
1.76(8)
1.66(8)
1.71(8)
1.77(8)
1.71(8)
1.70(7)
1.89(7)
1.85(7)
1.86(7)
–
–
–20.6 (3)
–11.3(3)
–9.7(3)
–10.6(3)
–13.9(3)
–9.5 (3)
–10.5(3)
–19.2(3)
–21.4 (3)
–18.6(3)
–
–
1.086
–
–
–
–
–
–
1.094
1.091
1.094
1.086
1.091
1.848
–
–
–
–
–
–
1.815
1.833
1.815
1.866
1.829
-22.460
–
–
–
–
–
–
-21.385
-21.809
-21.373
-23.055
-21.619
Table 4S. Cartesian coordinates of model optimized structure illustrated in Figure 3.
Atom
C
C
C
C
C
Ni
C
C
H
H
H
H
H
H
H
H
H
Ni
C
C
C
C
C
C
C
H
H
H
H
H
H
H
H
H
x/Å
–0.409879
–0.612256
–1.630277
–2.092205
–1.317459
–0.037014
0.869996
1.787173
2.087186
0.876480
0.454903
–2.894144
–1.396802
0.311642
–0.099013
2.499686
–2.047514
0.037361
–1.784750
-0.865017
0.616639
1.637485
2.089670
1.305759
0.402708
2.890315
1.376490
–0.323976
0.109517
–2.085460
–0.870137
–0.448860
2.061629
–2.497680
y/Å
–2.974590
–1.764515
–1.030290
–1.829774
–3.015602
–1.247926
–1.494599
–1.651378
–2.651467
–0.571849
–2.370255
–1.579928
–3.827311
–3.747927
–1.444906
–0.856154
–0.078662
1.246878
1.648941
1.489258
1.761103
1.035173
1.840289
3.020332
2.971015
1.597124
3.834136
3.737552
1.435929
2.649900
0.564369
2.363270
0.085003
0.854302
z/Å
0.588569
–0.109610
0.592299
1.690492
1.699227
1.910686
3.665361
2.609869
2.283223
4.246700
4.173638
2.379572
2.419027
0.334822
–1.012163
2.387057
0.277663
1.909713
2.614460
3.667124
–0.111015
0.596884
1.694585
1.698036
0.583977
2.387600
2.416541
0.324353
–1.014921
2.291602
4.245658
4.176580
0.286338
2.390334
6. Additional references
[1]
[2]
[3]
[4]
APEX2 package, Bruker AXS, Madison, WI, USA, 2010.
a) R. H. Blessing, J. Appl. Cryst. 1989, 22, 396; b) R. H. Blessing, Acta Cryst. 1995,
A51, 33; c)R. H. Blessing, J. Appl. Cryst. 1997, 30, 421.
G. M. Sheldrick, Acta Cryst. 2008, A64, 112.
H. Fuess, International Union of Crystallography, Chester, 2006.
Supplementary Material (ESI) for PCCP
This journal is © the Owner Societies 2011
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[19]
[20]
XD2006, A. Volkov, P. Macchi, L. J. Farrugia, C. Gatti, P. Mallinson, T. Richter, T.
Koritsanszky, 2006.
N. K. Hansen, P. Coppens, Acta Cryst. 1978, A34, 909.
F. H. Allen, O. Kennard, D. G. Watson, L. Brammer, A. G. Orpen, R. Taylor, J.
Chem. Soc. Perkin Trans. II 1987, 2, S1.
F. H. Allen, I. J. Bruno, Acta Cryst. 2010, B66, 380.
a) A. Ø. Madsen, J. Appl. Cryst. 2006, 39, 757; b) P. Munshi, A. Ø. Madsen, M. A.
Spackman, S. Larsen, R. Destro, Acta Cryst. 2008, A64, 465.
A. A. Hoser, P. M. Dominiak, K. Woźniak, Acta Cryst. 2009, A65, 300.
F. L. Hirshfeld, Acta Cryst. 1976, A32, 239.
L. J. Farrugia, C. Evans, D. Lentz, M. Roemer, J. Am. Chem. Soc. 2009, 131, 1251.
a) A. D. Becke, Phys. Rev. A 1988, 38, 3098; b) J. P. Perdew, Phys. Rev. B 1986, 33,
8822; c) J. P. Perdew, Phys. Rev. B 1986, 34, 7406.
Amsterdam Density Functional (ADF), SCM, Theoretical Chemistry, Vrije
Universiteit, Amsterdam, The Netherlands, 2009.
a) T. Ziegler, V. Tschinke, E. J. Baerends, J. G. Snijders, W. Ravenek, J. Phys. Chem.
1989, 36, 3050; b) J. G. Snijders, E. J. Baerends, Mol. Phys. 1978, 36, 1789; c) J. G.
Snijders, E. J. Baerends, P. Ros, Mol. Phys. 1979, 38, 1909.
a) E. J. Baerends, D. E. Ellis, P. Ros, Chem. Phys. 1973, 2, 41; b) E. J. Baerends, P.
Ros, Chem. Phys. 1973, 2, 52; c) G. te Velde, E. J. Baerends, J. Comput. Phys. 1992,
99, 84; d) G. te Velde, F. M. Bickelhaupt, E. J. Baerends, C. F. Guerra, S. J. A. van
Gisbergen, J. G. Snijders, T. Ziegler, J. Comput. Chem. 2001, 22, 931.
a) A. Michalak, M. Mitoraj, T. Ziegler, J. Phys. Chem. 2008, 112, 1933; b) M.
Mitoraj, A. Michalak, J. Mol. Model. 2007, 13, 347.
M. Mitoraj, A. Michalak, T. Ziegler, J. Chem. Theory Comput. 2009, 5, 962.
R. F. W. Bader, Atoms in Molecules - A Quantum Theory, Oxford University Press,
Oxford, 1990.
DGRID, M. Kohout, Dresden, 2010.