A MODEL CLASSICAL-STUDY OF NONLINEAR RESONANCE AND TORSIONAL ISOMERIZATION

A simple two degrees of freedom classical model of the nonlinear reson ance interaction between symmetric bond bending and torsional motion i n linearly bonded tetra-atomic molecules is investigated. The rate and mechanism of intramolecular vibrational energy redistribution at diff erent relative vibrational frequencies is evaluated, and comparison is made with quantum calculations. The rate of torsional isomerization i s compared to the prediction of transition stale theory, and related t o the observed intramolecular vibrational energy redistribution.