Rate Coefficients for the Collisional Removal of NO in the Neighboring a⁴P(u = 8) and B²P(u = 0) Levels

H. I. Bloemink, J. Lacoursière, R. A. Copeland, and T. G. Slanger

Aeronomy Group, Molecular Physics Laboratory
SRI International
Menlo Park, California 94025

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Abstract

The prevalence of NO emission from the u = 0 level of the B²P state in collision-controlled N + O recombination spectra is a consequence of the interaction of this level with the u = 8 level of the a⁴P state. Here we contrast and compare the loss kinetics of a⁴P(u = 8) and B²P(u = 0), finding that for all colliders except NO itself, the removal out of the vibrational level of the quartet state is substantially faster than that from the lowest vibrational level of the doublet state. Earlier estimates of the loss rate coefficients for the B²P(u = 0) level generated in afterglow systems have been much too large in many cases, presumably as a consequence of the fact that the a⁴P state is the B²P precursor.