Interstitial Motion During Radiation Damage and Sputtering Processes

There are two major models for the mechanism of interstitial motion away from the F centre during photon or low energy electron excitation of alkali halides. Previously these models of a focussed replacement collision sequence of halogen ions or a thermally activated H centre diffusion are considered to be alternatives. Some new detailed data on halogen ejection from alkali halides during low energy irradiation are reported which are relevant to this problem. A model is presented which offers an explanation for the data on halogen ejection: the energy spectrum, temperature dependence, and presence of molecular emission. Experiments which would further clarify the model are proposed.