Vibrational predissociation rates and final state distributions for He-ICIand He-I-2 using a computationally simple method

The vibrational predissociation rates of triatomic van der Waals complexes were investigated by a new, computationally simple method. The method is ba sed on three approximations: (a) metastable vibrationally excited states of the complex are described by the vibrational self-consistent field (VSCF) approximation, (b) the coupling among the rotational states of the dissocia ting diatomic fragment is treated by the infinite order sudden (IOS) approx imation, and (c) the vibrational transition that leads to dissociation is t reated by the distorted wave Born approximation (DWBA). The predissociation rates, the product rotational state distributions, and the lifetimes of vi brationally excited states of He-ICl and He-I-2 are all computed and are in reasonable agreement with other theoretical and/or experimental results. T he suggested VSCF-DWBA-IOS scheme is found to be a very simple but efficien t theoretical tool to investigate the dissociation dynamics of van der Waal s complexes.