Abstract: Barium fluoride crystals were colored electrolytically by using a pointed cathode at various temperatures, electric field strengths and time. At RT, the spectra of the crystals were systematically measured. No characteristic absorption bands were observed in the crystals before electrolytic coloration. Lots of F, FA and some unknown color centers were found in the colored crystals. By analysis of the spectra of the colored crystals at different temperatures, electric field strengths and time, the variation of the spectral band intensity with temperatures, electric field strengths and time was obtained. The formation mechanism of the color centers and the spectral band intensity variation mechanism with temperatures, electric field strengths and time were given.

Key words: Barium fluoride crystals were colored electrolytically by using a pointed cathode at various temperatures, electric field strengths and time. At RT, the spectra of the crystals were systematically measured. No characteristic absorption bands were observed in the crystals before electrolytic coloration. Lots of F, FA and some unknown color centers were found in the colored crystals. By analysis of the spectra of the colored crystals at different temperatures, electric field strengths and time, the variation of the spectral band intensity with temperatures, electric field strengths and time was obtained. The formation mechanism of the color centers and the spectral band intensity variation mechanism with temperatures, electric field strengths and time were given.