Theoretical study on the reaction of silylenoid H 2SiLiF with HF

Abstract

The reactions of the two most stable isomers, the three-membered ring ( Ra) and the p-complex ( Rb), of silylenoid H 2SiLiF with HF have been studied by G3(MP2) method, respectively. The insertion into H–F bond and the H 2-elimination channels were identified on each reaction surface. Natural bond orbital (NBO) analysis has been performed to study the effects of charge transfer and to understand the nature of different interactions between atoms and groups. Furthermore, the theoretical forward reaction rate constants in the temperature range 200–1200 K were computed by canonical variational transition state theory with small-curvature tunneling correction (CVT/SCT) method. It is concluded that three insertion channels of Ra and Rb ( Ra-I, Rb-I1 and Rb-I2) and the H 2-elimination channel of Ra ( Ra-E) would be four competitive reaction channels, the H 2-elimination channel of Rb ( Rb-E) could be negligible, and silane H 3SiF should be the major product. The small-curvature tunneling (SCT) correction effect plays an important role for the calculation of rate constants for the reactions.