Gamma ray induced modifications of quaternary silicate glasses

This paper reports the effects of gamma ray irradiation and glass composition on the optical and infrared spectra of quaternary silicate glasses. Experimental results reveal the formation of radiation-induced absorption bands in the visible region attributed to nonbridging oxygen hole centres. The band gap energy and the width of the energy tail above the mobility gap have been measured before and after irradiation. The decrease in the energy gap values has been discussed in terms of radiation-induced structural modifications and the glass composition. Changes in the infrared spectra with progressive gamma irradiation have been observed and explained with reference to the radiolysis of Si-O-Si bonds.