Impact of V₂O₅ and Gamma Ray Irradiation on The Optical and Structural FTIR Spectra of Lithium Phosphate Glass

Combined studies on prepared undoped lithium phosphate glass of the composition (Li₂O₃30-P₂O570 mol%) and derived samples containing additional dopants of V2O5 (0.4, 1, 2, 3, 4%). The glasses have been investigated using optical (UV-visible) and FTIR spectra before and after being gamma irradiated with a dose of 6 M rad (6x10⁴ Gy). The collective spectral properties have been employed to explore the states of vanadium ions in this specific host phosphate glass. The study extends to identify the impact of gamma ray’s irradiation on the glasses with and without V₂O₅. The optical spectrum of the undoped lithium phosphate glass shows distinct UV absorption which is accepted by many researchers to be due to unavoidable contaminated trace ferric ions while the absorption of the V₂O₅- doped samples exhibit additional bands within the visible region which are correlated with combined presence of lower valences of trivalent and tetravalent vanadium ions. Gamma irradiation on the undoped glass increases the UV absorption and produces an induced visible broad band and this behavior is related to some suggested photochemical reaction and the formation and induced visible of phosphorus oxygen hole center (POHC) band while the vanadium ions show some shielding behavior with the maintenance of the spectral curves as before irradiation in the visible region. The FITR spectra show pronounced and condensed vibrational peaks within the mid region due to Q² and Q³ phosphate groups beside few peaks due to OH, POH and water vibrations..

Keywords: Lithium phosphate glass; V₂O₅; Optical-FTIR spectra; Gamma irradiation