Vibrational relaxation and dissociation in nitrogen

Abstract

Calculations of the vibrational and dissociation transition probabilities are made for N2-N2 and N2-N collisions by means of a semiclassical N-state approximation. The flaws in previous techniques are reviewed, with special attention given to the prediction of overtones. The method presented ignores the effects of molecular rotation and employs a revised extended Rydberg intermolecular potential to describe diatom-diatom and diatom-atom collisions. The collision velocities investigated exhibit probabilities of less than unity by means of the N-state method. The continuum is quantized to treat dissociation, and the collision results demonstrate probability enhancements for V-V-T transitions in both bound-bound and bound-free transitions. The technique is of particular interest for the theoretical modeling of reentry flows such as those encountered in aerobraking maneuvers.