Estimation of complex formation rate constants for collisions between diatomic molecules Original Research Article

A recently proposed method for computing collision frequencies - or complex formation rate constants - for collisions between diatomic molecules is investigated. The method is based on a mapping procedure of the full interaction potential onto a spherically symmetric form followed by a simple Langevin-type calculation of the complex formation (or capture) rate constant. Both canonical and microcanonical versions of this effective potential theory are described and applied to three different systems: a dipole-dipole model system, the HF + HP system and the OH + HBr system. Comparisons are made with adiabatic capture and classical trajectory calculations.