Isomers of SiCl3Li

Silylanions: Inversion Barriers and NMR Chemical Shifts

“…In the neutral ion complexes, the inverted structures sometimes are more stable than the tetrahedral structures. This reversed stability has been reported for H 3 SiLi36 and for halogenated silyllithium and ‐sodium compounds37–39 in the gas phase. In the solid state or in solution, small energetic stabilities might be reversed as for H 3 SiNa 40.…”

“…They argue, however, that the order of stability should be reversed in solution. For the derivative with R=Cl,18 a preference for the inverted structure of 26.0 kcal mol −1 37 was obtained. Detailed density functional theory (DFT) studies on X n H 3− n SiM (M=Li, Na, X=F, Cl, Br) molecules showed an increased stability of the inverted forms with increasing number and size of the halogens 38, 39…”