Nonadiabatic molecular dynamics simulations of the photofragmentation and geminate recombination dynamics in size-selected I-2(-)center dot Ar-n cluster ions

We investigate the photodissociation, geminate recombination and relaxation dynamics in size-selected I-2(-).Ar-n cluster ions using a coupled quantum-classical molecular dynamics method and a model Hamiltonian gained from diatomics-in-ionic systems. We calculate photofragmentation yields of various charged product clusters of the dissociated I-.Ar-f or recombined I-2(-).Ar-f, forms as a function of precursor cluster size and find almost quantitative agreement with experimental results. The trends in photofragmentation are explained in terms of various participating electronically nonadiabatic channels coupled with vibrational relaxation on these different surfaces. We also explore the role of long range electrostatic interactions and underlying precursor cluster geometry on the photofragmentation dynamics. (C) 1997 American Institute of Physics.