Dynamics of excess electron migration, solvation, and spectra in polar molecular clusters

The dynamics of excess electron localization, migration, and solvation in water and ammonia clusters, and the time-resolved spectroscopic consequences of these processes, are investigated via computer simulations. In these simulations, the solvent evolves classically and the electron propagates in the ground state. The coupling between the polar molecular cluster and the electron is evaluated via the quantum expectation value of the electron-molecule interaction potential. Starting from an electron attached to a cold molecular cluster in a diffuse weakly bound surface state, temporal stages of the electron solvation and migration processes, leading to the formation of an internally solvated state, and the associated variations in the excitation spectra are described. The migration of the excess electron during the penetration is characterized by a nonhopping, polaronlike mechanism.