Theoretical study of the multiplet branching of the SD product in the S(D1)+D2→SD(Π2)+D reaction

Abstract

The statistical model of atom-diatom insertion reactions is combined with coupled-states capture theory to calculate integral cross sections for formation of specific rotational/fine-structure states of the SD product of the title reaction. The four electronic potential energy surfaces that correlate with the products (1,3A' and 1,3A") and an accurate description of the electronic and spin-orbit couplings between them have been determined from ab initio calculations. The dependence of the cross sections upon the product rotational quantum number shows a statistical behavior similar to that computed with the simple prior statistical model. We predict a significant preference for formation of the lower (F1) versus the upper (F2) spin-orbit manifold but essentially equal A' and A" Lambda-doublet populations. The computed SD v=0 rotational/fine-structure state distribution is in good agreement with the distribution measured experimentally for this reaction by Khachatrian and Dagdigian [J. Chem. Phys. 122, 024303 (2005)]. The calculations predict the F1: F2 spin-orbit population ratio to be slightly larger than experimentally observed.