Role of Fe2O3 and MoO3 content on Optical Properties of Lead Borate Glasses

Glasses with compositions xM.(40-x)PbO center dot 60B(2)O(3) (M=Fe2O3 and MoO3) have been synthesized by standard melt-quenching technique. The amorphous nature of the each sample was ascertained by XRD patterns. The absorption edge (lambda(cut-off)) shifts toward longer wavelengths with an increase in Fe2O3 as well as MoO3 content in the glass matrix. The Urbach's energy is used to characterize the degree of disorder in amorphous solids. The values of optical band gap energy for indirect allowed and forbidden transitions have been determined and it was found that it decreases faster in Fe2O3 based samples than the samples containing MoO3 Content. From these results, it was observed that Fe2O3 to be a better probe to generate non-bridging oxygens (NBOs) than MoO3 content in the present study.