ULTRASHORT DISSOCIATION AND RECOMBINATION DYNAMICS OF $I_{2}$ IN MATRIX Ar, A LINEAR CHAIN MODEL

Abstract

The photo-induced dissociation and recombination dynamics of $I_{2}(A/A^{\prime})$ embedded in low temperature matrix Ar are investigated theoretically in a linear chain model. This work is designed to simulate the recent femtosecond pumpprobe experiment by Apkarian and $co-workers^{1}$. The dynamics of the $I_{2}$ (subsystem) is treated quantum mechanically while the motion of the Ar matrix (bath) is described classically. The quantum dynamics of the subsystem is self-consistently coupled with the classical bath, allowing energy dissipation. Our calculations show substantial energy transfer and retention of coherence in the early stages of the recombination process, in agreement with experiment.