The estimation of vibrational predissociation lifetimes

Abstract

Analytical formulae for vibrational predissociation level positions and lifetimes due to interchannel coupling and quantum-mechanical tunnelling are derived from a few-channel approximation to a recent internal collision model. The generalisation to many channels suggests an approach to the estimation of very narrow resonances based on a bound-state diagonalisation supplemented by simple semiclassical tunnelling factors. The possibility of an interference mechanism leading to very narrow resonances is also indicated.