A Study of the Absorption Spectra of Cerium in Glasses

The absorption bands of cerium in trivalent and tetravalent states in silicate and phosphate glasses, whose exact positions are still open to discussion, and the effects introduced by the change of composition and of melting condition were investigated.For the measurement of the absorption spectra of silicate glasses with poor ultraviolet transmission the thickness of the sample plates was reduced to 0.12-0.02mm by polishing.The results obtained are as follows: (1) In the silicate glass consisting of K2O, BaO, and SiO2, Ce3+ gives a sharp and weak absorption band at 320mμ, whereas Ce4+ gives a broad and strong absorption band in ultraviolet region below 350mμ. (2) In the phosphate glass consisting of K2O, BaO, Al2O3 and P2O5, Ce3+ gives three sharp and weak absorption bands at 294, 245, and 227mμ, whereas Ce4+ gives a broad and strong absorption band in ultraviolet region, as before.