Temperature Dependence of Defect Production in KBr and KCl (I)

The rate of production of defects by ionizing radiation in Harshaw KBr and KCl has been studied as a function of temperature. It is found that the production rate increases in a fairly progressive manner between 81 and about 200 °K. A correlation is found between the increases in defect production and a progressive broadening of the V‐centre absorption envelopes formed at the various temperatures of irradiation. Studies of the growth of the major V‐centres responsible for these absorption envelopes show that they are interstitial defects. It is considered that the enhanced defect production results from an increased probability of interstitial trapping as the temperature of irradiation is raised, and that the interstitial defects are trapped in clusters, either intrinsic or nucleated by impurities.