Glasses with compositions (60x)V2O5–40TeO2–xSb2O3 with 0 6 x 6 10 (in mol%) have been prepared using usual melt quenching method. The position of the absorption edge and hence the values of the opti- cal band gap was found to depend on the glass composition. Using the Tauc model, the absorption spec- trum fitting method (ASF) was employed to obtain the optical band gap. This method requires only the measurement of the absorbance spectrum of the sample. For each sample, the width of the band tail was determined. Also, the density and glass transition temperature values indicate that the rigidity and pack- ing of the samples increase with increase in Sb2O3 concentration.
