Communication: Highly accurate ozone formation potential and implications for kinetics

Atmospheric ozone is formed by the O + O(2) exchange reaction followed by collisional stabilization of the O(3)* intermediate. The dynamics of the O + O(2) reaction and to a lesser extent the O(3) stabilization depend sensitively on the underlying potential energy surface, particularly in the asymptotic region. Highly accurate Davidson corrected multi-state multi-reference configuration interaction calculations reported here reveal that the minimal energy path for the formation of O(3) from O + O(2) is a monotonically decaying function of the atom-diatom distance and contains no "reef" feature found in previous ab initio calculations. The absence of a submerged barrier leads to an exchange rate constant with the correct temperature dependence and is in better agreement with experiment, as shown by quantum scattering calculations. (C) 2011 American Institute of Physics. [doi:10.1063/1.3632055]