A comparison of exact classical and quantum mechanical calculations of vibrational energy transfer. II. The effect of long-lived collision complexes

Abstract

Exact classical and quantum mechanical calculations of V–T relaxation were carried out for the model system He+O2(v=1). The diatomic molecule was treated as a harmonic oscillator, and a spherically symmetric Lennard-Jones intermolecular potential was assumed. The bin and two-moment methods were used to quantize the classical energy transfer. For a deep well both classical and quantal calculations showed evidence of complex formation. In this case inelastic transitions were classically allowed even at low collision energies. The classical transition probabilities generally agreed within a factor of 2 with the quantal results. The final energy distribution of the complex trajectories was not completely random, as compared with the information-theoretic prior expectation.