A simple matrix model of intramolecular vibrational redistribution and its implications

A multiple-range local matrix model for IVR is applied to systems with up to 100000 active states. Applications include calculation of IVR transients and high-resolution spectra of molecular models for vibrationally excited 1-propyne and trihalomethanes. The model bridges recent statistical theories and detailed quantum simulations on specific systems, and several different IVR regimes can be qualitatively distinguished. In many cases, characteristic deviations from exponential decay behaviour and/or the Golden Rule are observed.