Fragmentation mechanisms from three-dimensional wave packet studies: Vibrational predissociation of NeCl2, HeCl2, NeICl, and HeICl

Abstract

We present three‐dimensional, time‐dependent quantum studies on the van der Waals vibrational predissociation reactions of NeCl₂, HeCl₂, NeICl, and HeICl. A wave packet/basis set expansion approach is employed. The results for these systems agree reasonably well with experiment and time‐independent quantum calculations, where available. The similarities and differences among the four systems are explored by detailed inspection of the propagating wave function. The rotational product distributions can be understood in terms of a unified fragmentation mechanism that depends on the product of the initial probability density with a classical force, and short time dynamics. Quantum interference effects are shown to play an important role in the helium cases. A semiclassical model is also advanced to account for some features of the product distributions.