OPTICAL AND SPECTROSCOPIC STUDIES OF Fe₂O₃-Bi₂O₃-B₂O₃:V₂O₅ GLASSES

Abstract

The glasses of compositions x Fe 2 O 3 ⋅ (40 - x) Bi 2 O 3 ⋅60 B 2 O 3 ⋅2 V 2 O 5 have been prepared by the standard melt-quenching technique. Amorphous nature of these samples is ascertained by XRD patterns. The presence of BO 3 and BO 4 units is identified by IR spectra of glass samples. The absorption edge (λ cut-off ) shifts toward longer wavelengths with an increase in Fe 2 O 3 content in the glass matrix. The values of optical band gap energy for indirect allowed and forbidden transitions have been determined and it is found to decrease with increase in transition metal ions. The Urbach's energy is used to characterize the degree of disorder in amorphous solids.