Arrhenius Parameters for the Abstraction Reactions of Methyl Radicals with Silanes

摘要

Arrhenius rate parameters for the abstraction reactions of methyl radicals, produced by the photolysis of azomethane, with SiH4, SiD4, Si2H6, Si2D6andphgr;SiD3were determined in competition with recombination. Silanes are more reactive than their hydrocarbon counterparts, and the increased reactivity is due to lower activation energies, theAfactors being similar. The experimental values ofEahave been compared to those calculated by the bondhyphen;energyndash;bondhyphen;order method using a simple threehyphen;masshyphen;point model. Calculated kinetic isotope effects, based on absolute reaction rate theory, have been compared with experimental results.