Abstract
Binary tellurite glass systems of the forms TeO2(100−x)-xAnOm where AnOm = La2O3 or V2O5 and x = 5 to 20 for La2O3 and 10 to 50 for V2O5 were prepared. UV-spectra of these glasses were recorded in the range of 200–700 nm at room temperature. The optical energy gaps Eoptical and $E_{\rm tail}$ have been calculated from the optical absorption edge. UV cut-off and IR cut-off have been measured. Calculations of the oxide ion average polarizability ($\alpha_0^{2-}$) and optical basicity (Λ) have been done.