Effect of gamma radiation on some optical and electrical properties of lithium bismuth silicate glasses

Lithium bismuth silicate glasses with the composition of; 68% SiO₂, 20% Bi₂O₃, 8% Li₂O₃, 4% Na₂O doped with either 2% PbO, BaO or SrO (all in wt%) were studied to investigate some of their optical and electrical properties before and after different doses of gamma radiation. Density, oxygen packing density OPD, molar and specific volumes, optical UV absorption, optical energy gap, electrical conductivity and dielectric measurements were measured and discussed in this study regarding the effect of gamma radiation. The results showed that all glasses were more affected at the higher radiation dose (100 kGy) than the lower radiation dose (50 kGy) because of the creation of more defects and non- bridging oxygens NBOs at the higher dose. In spite of that, Pb²⁺ ions containing glass revealed better properties to resist gamma radiation than glasses containing either Ba²⁺ or Sr²⁺ ions because of its highly compacted structure and the low concentration of NBOs, defects or vacancies as well as the high polarizability of Pb²⁺ ions that plays an effective role in enhancing the glass optical and electrical properties.