Theoretical studies of H+H2 reactive scattering

Abstract

The H + H₂ reactive scattering problem was studied quantum mechanically in three dimensions by the close‐coupling technique. The ground vibrational state and a set of up to seven rotational states were included in the basis for both the initial and the final channels. The interaction of the three particles was described by the Porter‐Karplus surface in order to permit comparison with classical calculations. A method was developed for solving the sets of coupled integrodifferential equations that appear in the close‐coupling approach to rearrangement scattering. Transition probabilities for reactions involving the 0, 1, 2 rotational states of H₂ were calculated for relative kinetic energies from 0.20 to 0.50 eV. Differential cross sections were estimated for the 0→1 rotational transition. The results were compared with three‐dimensional classical studies as well as other quantum mechanical results. A significantly lower threshold for reaction was obtained in the present work both with respect to the three‐dimensional classical results and a distorted wave Born calculation for reactive scattering from the same surface.