Kinetic studies of the reaction of Cl atoms with SiH4

Abstract

The reaction kinetics of chlorine atoms with silane has been studied over the temperature range 273–363 K using the very low pressure reactor technique. The reaction proceeds via a hydrogen-atom abstraction and leads to SiH₃ and HCl products. The absolute rate constant was found to be independent of temperature with a value k₁=(3.25 ± 0.40)× 10^–10 cm³ molecule^–1 s^–1. Ab initio calculations at the MP2/6–311G(d,p) level of theory did not show any evidence for the formation of an intermediate SiH₄–Cl adduct. The thermochemical version of conventional transition-state theory indicated that the transition-state geometry is almost linear, with a Si—H—Cl angle of ca. 170°.