Infrared spectra of Fe2O3–PbO–P2O5 glasses

The structure of three Fe2O3–PbO–P2O5 glass groups has been investigated using IR spectroscopy. The intensity and frequency of the IR bands have been measured to follow the changes in the structural groups in the glass matrix. The spectral analyses revealed that the short-range order of the glassy matrix is strongly affected by the addition of PbO and/or Fe2O3 to P2O5 glass. The changes observed in IR spectra of PbO–P2O5 glasses are related to the dual role of lead ions as a glass former and modifier. The results revealed that there are critical concentrations of Fe2O3 at which iron ions change their local structure. The critical composition depends strongly on the content of both PbO and P2O5 in glass. The fraction of POP linkages is constant for O/P > 3, i.e. above the critical concentration of Fe2O3.