Luminescence from Sodium Chloride

Abstract

The x-ray-induced luminescence from NaCl has been studied in the range from 2.1 to 5.2 ev and in certain cases correlated with optically induced luminescence. The intensity and spectral distribution of the x-ray-induced luminescence was found to be dependent on the previous heat treatment received by the crystal. Before heating, bands are present at 2.25, 3.1, and 5.0 ev; afterwards, strong new bands appear at 2.45 and 3.5 ev and the intensity of the 5.0-ev band is increased. Prolonged x-irradiation reduces most of the effects of heat treatment; however, following such prolonged x-irradiation, a relatively strong band is present at 2.9 ev.