Mechanics of Atomic Recombination Reactions

Abstract

A treatment is developed by means of which it is possible to calculate an equilibrium constant for the formation of a collision complex from a pair of chemically interacting atoms. For iodine atoms, this leads to a value of the rate constant for I+I+M→I₂+M, if the mechanism is 2I⇌I₂^*(¹Σ), I₂^*+M→I₂+M. The rate constant so calculated agrees with that obtained by a statistical procedure [J. Keck, J. Chem. Phys. 29, 410 (1958)]. The calculation also furnishes enough information about the mechanical details of collisions so that the contribution of molecular states other than ¹Σ to recombination may be deduced. As a result a fairly conclusive discussion may be given of the plausibility of the various detailed mechanisms thus far suggested. A most likely mechanism and a possible calculation based on it are proposed.