FORMATION TIME OF F-CENTERS IN ALKALI-HALIDES

It is argued that in most alkali halides an appreciable fraction of the self-trapped excitons may undergo non-radiative transitions from vibrationally excited states of B3u to the A1g state during the relaxation of the self-trapped excitons created by ionizing radiation. Numerical calculations show that the non-radiative transition probabilities, from vibrational levels of B3u near or above the crossing point of the A1g and B3u potential curves to the A1g state, are consistent with the observed formation times of F centers in various alkali halides. The exceptional case of KI is also discussed. © 1979.