Diatomic molecules elastic scattering

Here we shall be concerned with the interaction of inacming diatomic molecules (H-/ 0.) with either types of potential energy wells The molecular InteractJjon (responsible for elastic and direct-inelastic scattering with extremely short residence times of the irpinglng molecules in the potential) and the chemisorptive interaction (leading to dissociative adsorption and associative desorption, reflectively, and associated with H (D) atoms trapped in the chemisorption potential for an appreci le time). 

For a structureless continuum (i.e., in the absence of resonances), assuming that the scattering projection of the potential can only induce elastic scattering, the channel phase vanishes. The simplest model of this scenario is depicted schematically in Fig. 5a. Here we consider direct dissociation of a diatomic molecule, assuming that there are no nonadiabatic couplings, hence no inelastic scattering. This limit was observed experimentally (e.g., in ionization of H2S). 

Microscopic and Macroscopic Kinetics.— Any bimolecular collision must lead to one of three general results elastic scattering, energy transfer, or chemical reaction. Here we are concerned with systems where diemical reaction is at least possible. The simplest such system comprises an atom (A) colliding with a diatomic molecule (BQ and collisions of this type are featured prominently in the ranainder of this article. 

An important development has occurred in the field of elastic scattering of ions. Studies of rainbow phenomena yielded data on interparticle potentials of noble gas-proton systems, " " as well as proton-diatomic molecules, H2 -Kr, and H2 -Ar average potential parameters. 

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