Arrhenius parameters for H+(CH3)4-nSiHn, n=1–3

Abstract

Rate constants for the reactions of H atoms with the methylsilanes, (CH₃)_4-nSiH_n, n=1–3, have been measured over the temperature range 298–580 K in flash photolysis experiments in which H atoms were produced by the mercury-sensitized photolysis of H₂ and monitored by Lyman-α absorption. The values obtained, for n=1–3, respectively, are given by, The results show that methyl substitution increases the reactivity of the Si–H bond towards H atom attack. Comparison is made with previously published data, and with attack by other atoms and free radicals.