On the nature of pre-existing states for an excess electron in water

Abstract

The nature of the electronic eigenstates for an excess electron in pure water in the absence of solvent reorganization is investigated using solvent configurations generated from molecular dynamics simulation of liquid water at 283 K and a previously developed electron-water molecule pseudopotential. The electronic density of states is found to exhibit a significant tail at lower energies that is comprised of physically localized states, although these states are, at best, only shallowly trapped with respect to the free electron. The electronic absorption spectrum associated with the set of ground electronic states is found to be a diffuse infrared band in general accord with the spectrum observed experimentally at the earliest times following creation of an excess electron in water. However, this spectrum is insensitive to the degree of localization of the initial state, indicating that this result does not discriminate strongly among alternative descriptions of the electronic state present experimentally.