The spectroscopic investigations on Ni2+ ions in PbO-As2O3 glasses

PbO-As2O3 glasses containing different concentrations of NiO ranging from 0 to 1 mol% (in steps of 0.2) were prepared. The optical absorption and thermoluminescence have been carried out on these glasses. The analysis of the optical absorption spectra indicates the presence of Ni2+ ions in both tetrahedral and octahedral positions. The increase in the concentration of NiO in the glass matrix shows a gradual transformation of nickel ions from tetrahedral positions to octahedral positions in the glass network. TL light output of the X-ray irradiated glasses has exhibited a glow peak at 353 K in addition to the conventional peak due to the recombination of electron-hole centres; this glow peak is identified due to 3T2→ 3A2 emission transition of octahedral Ni2+ ions. The present study indicates an increasing presence of octahedral (lasing) Ni2+ ions in these glasses with the concentration of NiO.