Arrhenius parameters for silene insertion reactions

Abstract

Co-pyrolyses of disilane with monosilane or with hydrogen have been conducted over wide ranges to temperature, pressure and mixture composition. The following Arrhenius parameters for the silene insertion reactions have been calculated from the rate data and thermochemical information: SiH₂+ SiH₄→ Si₂ H₆(– 1), SiH₂+ Si2H₆→ Si₃ H₈(2), SiH₂+ H₂→ SiH₄(5), log(A_–1/l. mol^–1 s^–1)= 9.7, E_–1= 5400 J mol^–1; log(A₂/l. mol^–1 s^–1)= 9.85, E₂= 1615 J mol^–1; log(A₅/l. mol^–1 s^–1)= 9.1; E₅= 23 000 J mol^–1. Disilane is shown to be a suitable source of silene and the data presented for k₂ and E₂ now permit extension of the co-pyrolysis method to the evaluation of the rate parameters of a range of other silene insertion reactions.