A theoretical study of the reactions of S( [formula omitted])+H 2, HD, D 2

Abstract

A collision complex model has been applied to describe the reactions of S( 1 D )+H 2, HD, and D 2. The reactions are assumed to proceed exclusively through an insertion mechanism on the lowest 1 A′ adiabatic potential surface at 1–10 kcal/mol. The transition states of the two dissociation channels for the intermediate H 2S have been located by the variational RRKM theory based on ab initio potential energy surfaces. The calculated isotope ordering of the reaction cross-sections is interpreted as a strong indication of the dominating role played by the dynamic effects in the single collision environments. The derived thermal rate constant of S( 1 D )+H 2 at 300 K agrees reasonably well with the experimental value.