Modelling of the Self-Trapped Excition π Luminescence in Alkali Halides

On the basis of recent works which show that the self-trapped exciton in alkali halides and other ionic halides are essentially a nearest neighbour pair of F – H centers, we show that the emission band peak energy and lifetime of the π band in pure and heavier halogen doped alkali halides are correlated to the off-center shift of V k -core. It is suggested that parameters of the π emission bands can be predicted on the basis of this correlation.