On the relation between collinear and three dimensional rate constants associated with vibrational energy transfer in diatom–diatom collisions

Abstract

An information-theoretic approach to the transformation of collinear energy transfer rates for diatom–diatom collisions to 3-D results is given. The present work is an extension of the Wassam–Levine 1-D to 3-D conversion scheme for atom–diatom collisions. An expression for the 3-D detailed rate constants, at a well-defined rotational-translational temperature, is obtained. This expression is employed in a numerical analysis of the temperature dependence of vibrational relaxation in O2 (v=1) :H2, HCL (v=1) :H2, O2 (v=1) :O2, and CO (v=1) :CO. 3-D rate constants are characterized in terms of V-T and V-V-T sum rules and suprisal plots. We find that the minimum in the suprisal does not occur in the region of resonance vibrational energy exchange.