TY - JOUR
T1 - Structure, spectra, and intramolecular motions of 1,4-bis(trimethylsilyl)-1,3-butadiyne
T2 - An electron diffraction study using the results of spectral analysis based on scaled quantum-chemical force field for calculating vibrational effects
AU - Traetteberg, M.
AU - Khaikin, L. S.
AU - Grikina, O. E.
AU - Liebman, J. F.
AU - Hulce, M.
N1 - Funding Information:
The authors are grateful to the Russian Foundation for Basic Research (Project No. 99-03-32511a) for financial support of works fulfilled at the Department of Chemistry, Moscow State University. We want to thank Pirkko Bakken for skilful technical assistance.
PY - 2001/1/7
Y1 - 2001/1/7
N2 - The molecular structure of 1,4-bis(trimethylsilyl)-1,3-butadiyne has been studied by the gas electron diffraction method and by ab initio calculations at the RHF and MP2 levels. A scaled quantum-chemical force field was used to interpret the vibrational spectra. The root-mean-square vibrational amplitudes and harmonic shrinkage corrections were calculated taking into account non-linear relations between Cartesian and internal vibrational co-ordinates at the level of first-order perturbation theory (h1) and with the use of the traditional scheme (h0). The total energies of the D3d and D3h conformers differ by about 1 cal mol-1 (0.4 cm-1) which implies virtually free internal rotation. It has been shown that the flexibility of the linear fragment in (CH3)3Si-C≡C-C≡C-Si (CH3)3 has increased considerably compared to that in (CH3)3Si-C≡C-Si(CH3)3.
AB - The molecular structure of 1,4-bis(trimethylsilyl)-1,3-butadiyne has been studied by the gas electron diffraction method and by ab initio calculations at the RHF and MP2 levels. A scaled quantum-chemical force field was used to interpret the vibrational spectra. The root-mean-square vibrational amplitudes and harmonic shrinkage corrections were calculated taking into account non-linear relations between Cartesian and internal vibrational co-ordinates at the level of first-order perturbation theory (h1) and with the use of the traditional scheme (h0). The total energies of the D3d and D3h conformers differ by about 1 cal mol-1 (0.4 cm-1) which implies virtually free internal rotation. It has been shown that the flexibility of the linear fragment in (CH3)3Si-C≡C-C≡C-Si (CH3)3 has increased considerably compared to that in (CH3)3Si-C≡C-Si(CH3)3.
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U2 - 10.1016/S0022-2860(00)00709-2
DO - 10.1016/S0022-2860(00)00709-2
M3 - Article
AN - SCOPUS:0035819272
VL - 559
SP - 295
EP - 313
JO - Journal of Molecular Structure
JF - Journal of Molecular Structure
SN - 0022-2860
IS - 1-3
ER -