Theoretical Studies of the Reaction Paths and Rate Constants for SiH4 + H System

Abstract

The reaction of SiH₄ with H has been studied using the three ab initio levels. The structure of the potential energy surface includes the reactants, the prior complex, the transition state, the postcomplex and the product, are reported. Along the reaction coordinates, the dynamic potential wells correspond to the Feshbach resonance. The rate constants are calculated using the TST (CVT, ICVT) methods with the SCT correction. Rate constants in the temperature range of 200- 1600 K were reported at the G2//QCISD/6-311+G(df,pd) level and exhibits typical non-Arrhenius behaviour. The viriational effect on the values of rate constant is small and the tunneling correction is important in the calculation of rate constants in the lower temperature range. The three parameters expression in the range 200-1600 K is cm³ mol^-1. The calculated ICVT/SCT rate constants are in good agreement with the available experimental data.