Solvent-induced caging submitted to World Scientific 9/14/00 : 10:38 AM 1/10 SOLVENT INDUCED CAGE RECOMBINATION IN CLUSTER IONS: EXPERIMENTAL AND THEORETICAL INVESTIGATIONS

Photofragmentation of size-selected I2(CO2)n cluster ions and the subsequent cage recombination of the photodissociated I2 chromophore are observed to occur with high efficiency and on a ps time scale, for even partially solvated ions. This result is observed for dissociation on either ground state (I– + I) or spin-orbit excited (I– + I*) state surfaces. With intimate interplay between theory and experiment, we deduce the importance of solvent induced perturbation of the electronic structure of the chromophore. The dissociation dynamics are well described by a simulation that incorporates non-adiabatic curve crossings and solvent perturbation of the electronic structure within a classical molecular dynamics simulation. When the full dynamics are reduced to a solute and a solvent coordinate, a Marcus-like picture of solvent asymmetry-induced electron transfer emerges as an accurate description of the cage recombination process.