The transition-state region of the O((3)P)+O(2)((3)Sigma(g) (-)) potential energy surface.

Abstract

New electronic structure calculations for the transition-state region of the lowest ozone potential energy surface are reported. A two-dimensional potential energy surface in the asymptotic channel is calculated with the O(2) bond distance being fixed. The calculations are performed at the multireference average quadratic coupled cluster level of theory using full-valence complete active space self-consistent field wave functions and the augmented correlation consistent polarized V6Z atomic basis set. The general shape of the potential energy surface as predicted in earlier studies, that is, a narrow transition state below the O+O(2) asymptote, is confirmed by the present calculations. The transition state is 181 cm(-1) below the asymptote and 72 cm(-1) above the van der Waals-like minimum. The changes in the O+O(2)-->O(3) (*) capture cross section and rate constant when the new potential energy surface is employed are investigated by means of classical trajectory calculations.