A comparison of classical and quantum mechanical calculations of vibrational energy transfer. III. Use of the forced quantum oscillator and moment methods for quantization of product state distributions

Abstract

Vibrational transition probabilities calculated using the semiclassical forced quantum oscillator model and the information theoretic moment method were compared with exact quantal results in two model systems. In both cases the moment method was generally more accurate. Under conditions leading to a large distortion of the molecular force constant, the forced oscillator model was found to be in significant error. At low collision energies with two or three open states the moment method was inaccurate, and the forced oscillator model is preferred.