A theoretical study of the effects of vibration on the reaction O 3+NO→O2+NO2

Abstract

A series of model potential energy surfaces for the reaction O 3+NO→O2+NO2 is described. Nuclear geometry is unconstrained: The surfaces are nine dimensional. However, the possible interaction of more than one electronic surface has not been included. The model surfaces include various exoergicities, transition state geometries, and overall reaction topologies. Classical trajectories have been used to describe the dynamics on these surfaces. A variety of initial conditions, including selective excitation of vibrational modes of the ozone molecule, has been included. While translational and vibrational energy have distinctive effects on the reaction, no mode-specific enhancement of the reaction cross section was observed for any of the model functions. This is interpreted to result from the high degree of coupling of the internal coordinates to the reaction path and to the multidimensional curvature of the reaction coordinate. The results suggest caution in using prior studies of triatomic exchange reactions to predict behavior of these larger systems or as a guide in inferring information about the details of the potential energy function from the observed reaction properties. The relationship of these model studies to the actual O 3+NO system is discussed. © 1981 American Institute of Physics.