Production and conversion of color centers in OH −-doped KCl polycrystals colored electrolytically

Abstract

OH −-doped KCl polycrystals are colored electrolytically by using a pointed cathode and a flat anode at various temperatures and voltages. Characteristic O −, OH −, U, U A and Cu + absorption peaks are observed in resolved absorption spectra of uncolored polycrystals. Characteristic V 2, V 3, Cu +, O 2−– V a + , I 2 - , I 2, H 2O − and F spectral bands are observed at room temperature in Kubelka–Munk functions of colored polycrystals. Current–time curve for electrolytic coloration of an OH −-doped KCl polycrystal and its relationship with electrolytic coloration process are given. Production and conversion of color centers are explained.