Optical spectra of localized excess electrons in alkali halide clusters

Abstract

Excess electrons attached to small alkali halide clusters give rise to optical-absorption bands whose characteristics are highly specific to the mode of electron localization. Optical spectra measured by cluster beam and resonant two-photon ionization spectroscopy agree well with predictions of coupled classical-quantum simulations, and are interpreted in terms of two localization modes: surface F-center and diffuse surface states.