Dielectric properties of PbO–P2O5–As2O3 glass system with Ga2O3 as additive

PbO–P2O5–As2O3 glasses containing different concentrations of Ga2O3 (ranging from 0 to 5 mol%) were prepared. Dielectric properties (constant ε ′ , loss tan δ , ac conductivity σ a c over a range of frequency and temperature) of these glasses have been investigated. The analysis of the results of these studies together with the data on spectroscopic studies (optical absorption, infrared and Raman spectra) indicated that there is a gradual transformation of gallium ions from octahedral positions to tetrahedral positions, as the concentration of Ga2O3 is increased up to 4.0 mol%. Beyond this concentration, the tetrahedral occupancy of gallium ions however, seemed to be low.