V Centers in KI Crystals Containing Excess Iodine

摘要: Optical and thermal bleaching of the V 2 3 bands were investigated for additively- or electrolytically-colored KI crystals. After -light irradiation at 85 K, absorption formed 430 800 nm in company with an increase near fundamental-absorption edge; while, after same 125 α band a peak about 330 simultaneously. Changes intensities among these caused subsequent optical treatments; changes always accompanied. Upon polarized light, exhibited [100] anisotropy, whose maximum was shifted to 325 nm. On assumption that cation vacancies are introduced halogen-excess crystals, probable models centers discussed then photochemical interpreted by them.