Primary Reaction Channels and Kinetics of the Thermal Decomposition of Phenylsilane

Article abstract of DOI:10.1021/j100023a015

The thermally induced decomposition of phenylsilane has been investigated by three different experimental methods: a static method, a comparative rate-single pulse shock tube (CR-SPST) method, and a very low-pressure pyrolysis (VLPP) method.Decomposition is mainly heterogeneous under static conditions but appears homogeneous in the other two systems.Homogeneous dissociations occur by two channels with yields, PhSiH3<*>H2+PhSiH, φ₁ ca. 0.84; PhSiH3<*>PhH+SiH2, φ₂ ca.0.16 +/-0.04.Coupling of CR-SPST and homogeneous static reactor data spanning temperatures from 693 to 1236 K for the benzene formation channel and adjusting for falloff by RRKM methods gives high-pressure Arrhenius parameters of A₁ = 10^14.0+/-0.4, E₁ = 59.3 +/- 2.1 and A₂ = 10^13.9+/-0.2, E₂ = 62.0 +/- 0.9 (A in s^-1 and E in kcal/mol) for the two primary dissociation channels.These parameters yield RRKM calculated rate constant under VLPP conditions which agree within the errors with experimental rate constants.