Nickel ion as a structural probe in PbO-Bi2O3-B2O3 glass system by means of spectroscopic and dielectric studies

PbO- Bi2O3-B2O3 glasses containing different concentrations of NiO (ranging from 0 to 1.5 mol%) are prepared. A number of studies viz., spectroscopic (infrared, optical absorption spectra), magnetic susceptibility and dielectric properties (constant ε′, loss tan δ, ac conductivity σac over a range of frequency and temperature) of these glasses have been carried out. The optical absorption, magnetic susceptibility and IR spectral studies point out that nickel ions occupy both tetrahedral and octahedral positions in the glass network; the later positions seem to be dominant when the concentration of NiO is raised beyond 1.0 mol% in the glass matrix. The studies of dielectric properties reveal that the presence of nickel oxide in the glass network causes a considerable improvement in the insulating strength of these glasses when the concentration of NiO ∼1.0 mol%. The analysis of the results of all these studies further indicate that the glasses containing more than 1.0 mol% of NiO are suitable for getting laser emission due to 3T2(F)→3A2(F) transition in NIR region.