Collinear classical dynamics on a chemically accurate H+H₂ potential energy surface

Abstract

Exchange in the hydrogen atom-molecule systemiis investigated via classical collinear dynamics on the Yates-Lester potential energy surface. A threshold kinetic energy of 6.4762 kcal/mole (0.2808 eV) is determined. Exchange probabilities are found to be, in general, slightly less than those obtained using the energy surface of Shavitt, Stevens, Minn, and Karplus. Energy banding is observed and discontinuities in the transition region are attributed to snarled trajectories. Reaction probabilities for all possible combinations of H, D, and T are determined. Isotopic variations in reaction probability are explained in terms of the mass-dependent skew of the potential surface and differences in zero-point vibrational energy. Copyright © 1977 American Institute of Physics.