Abstract
Alkaline earth binary borate glasses with the composition of (100-x) B2O3 + X (BaO, CaO, SrO) where x=22, 32 or 42 wt. % were prepared by melting annealing technique. Some of their physical and spectroscopic properties have been studied before and after gamma irradiation such as Density, oxygen packing density, molar and specific volumes, as well as optical UV-visible absorption, optical energy gap (Eopt), FTIR and ESR spectroscopy. The UV-visible spectra show a shifting of the optical edge to higher wavelengths with increasing the polarizability of the introduced modifier ion and the dose of gamma radiation. FTIR spectra show the vibrational bands of the structural borate groups; the triangular BO3 and tetrahedral BO4 units at 1200-1600 cm-1 and 800-1200 cm-1 respectively. ESR spectra show a constant behavior of the glasses at the low doses of radiation up to 60 kGy but show high effect of radiation at the higher doses due to the formation of more paramagnetic defects and free radicals.