Differential Cross Sections for the H + H 2 S → H 2 + SH Reaction: A Full-Dimensional State-to-State Quantum Dynamics Study.

We utilized the time-dependent wave packet approach to compute the first full-dimensional (6D) state-to-state differential cross sections (DCSs) for the title reaction with the initial nonrotating H 2 S in the ground and the (100) and (001) vibrational excited states. It is found that the fundamental symmetric and asymmetric stretching excitations of H 2 S exhibit almost the same influence on the DCS, but unlike the H + H 2 O → H 2 + OH reaction, they greatly increase the vibrational excitation of both the H 2 and SH products. The hot vibrational state distributions of H 2 are consistent with the prediction of product energy disposal by Polanyi's rules for an early barrier reaction. Because the incident H atom reacts strongly with both the ground and excited S-H states, the large populations of product SH( v 2 = 1), which are very close to the relative reactivity of the initial S-H( v = 0) state, can still be explained by the local mode picture for H 2 S and the nonreacting SH bond's spectator nature.