Journal of Physics B Atomic and Molecular Physics
An investigation of the critical potential strengths for binding in a model collinear triatomic system
A P Clark, A S Dickinson
Abstract
Close-coupling calculations have been performed to investigate the formation of three-particle bound states in a model collinear system. A generalization of Levinson's theorem (1966) is employed to determine the critical potential strengths necessary for the existence of the triatomic states. The system consists of an atom interacting through a Morse potential with a diatomic molecule bound by a harmonic potential. Comparisons are made with classical phase-space and S-matrix theory and with quantum-mechanical variational and perturbation calculations. When only a few bound states are involved it is shown that the quantal approximations are more accurate than the classical results.