Ab initio Study on Structures and Isomerization of Magnesium Fluorosilylenoid H2SiFMgF

作者:Zhang, Yi-jian; Li, Mei-jiang; Lai, Guo-qiao; Feng, Da-cheng; Feng, Sheng-yu*
来源:Chinese Journal of Chemical Physics, 2008, 21(6): 541-546.
DOI:10.1088/1674-0068/21/06/541-546

摘要

The structures and isomerization of magnesium fluorosilylenoid H2SiFMgF were investigated by ab initio molecular orbital theory. Four equilibrium structures and three isomeric transition states were located and fully optimized at the B3LYP/6-31G(d,p) and G3MP2B3 levels, respectively. Based on the B3LYP/6-31G(d,p) optimized geometries, harmonic frequencies of various structures were obtained and Si-29 chemical shifts were calculated. The solvent effects were investigated by means of the, polarizable continuum model using THF as a solvent at B3LYP/6-31G(d,p) level. Isomerization paths for isomers were confirmed by intrinsic reaction coordinate calculations. The calculated results show that tetrahedral structure has the lowest; energy and is the most stable; tetrahedral, three-membered ring, and p-complex structures are suggested to be the experimentally detectable ones; and sigma-complex structure has the highest energy and will not exist.