Abstract

We report experimental studies of the solvent effect on the femtosecond dynamics of the dissociation and recombination of iodine in the gas-to-liquid transition region. In these experiments, the pressure of the solvent (helium, neon, argon and krypton) spans the range from 0 to 2500 bar, corresponding to solvent densities from the ideal gas-phase limit to the liquid-like fluid regime. Using femtosecond pump-probe spectroscopy with fixed 60 fs pump (620 nm) and continuously tunable probe pulses (270 to 400 nm), three phenomena are systematically studied: the dephasing of the coherent nuclear motion in the bound B state, the collision-induced B state predissociation and the gemmate recombination of the dissociating iodine atoms onto the weakly bound A/A′-states.

© 1996 IEEE