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Updated: Jun 25, 2026

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Rotational spectra and conformational analysis of diethylsilane and diethyldifluorosilane
Sean A Peebles1, Michal M Serafin, Rebecca A Peebles
1Department of Chemistry, Eastern Illinois University, 600 Lincoln Avenue, Charleston, Illinois 61920, USA. sapeebles@eiu.edu
Abstract:
The rotational spectra belonging to the (28)Si isotopologue for three conformers of diethyldifluorosilane (Et(2)SiF(2)) and three conformers of diethylsilane (Et(2)SiH(2)) have been measured between 4 and 17 GHz by using pulsed-jet Fourier-transform microwave spectroscopy. Rotational spectra for the gauche-gauche, trans-trans, and trans-gauche conformers were identified for both molecules, while the significantly higher energy gauche-gauche' conformer was not observed. Ab initio calculations at the MP2(Full)/6-311+G(2d,2p) and MP2(Full)/6-311+G(2df,2pd) levels for the fluorine and the hydrogen analogues, respectively, provided rotational constants, dipole moment components, and the relative energies of the conformers to assist in the spectral assignment. In both molecules, the gauche-gauche conformer was identified by the ab initio calculations as the most stable. Agreement of the ab initio rotational constants with those from experiment was at worst 5%, with most rotational constants being predicted to within 2%.
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