Abstract
Li2O center dot 0.25Fe(2)O(3)center dot 0.25NiO center dot 1.5SiO(2) glass was prepared with and without 5 wt % sulfur (5) while melting the mixture of the starting materials at 1350 C for 1 h in air. A part of the as-prepared glass was heat treated for 1 h near its crystallization temperature (T-c) as determined from differential thermal analysis. Each glass was also investigated by means of Mbssbauer spectroscopy, X-ray diffraction, FTIR, and DC conductivity. The Mbssbauer spectra showed ionic Fe2+ and Fe3+ species in the glass as well as in the precipitated phase obtained after heat treatment. XRD patterns demonstrated the glassy phase formation in the as-quenched samples irrespective of the presence of sulfur. The heat treated samples showed different precipitated phases containing iron particles of nanometer size. The electric conductivity measurements showed that sulfur-doped samples had high values of (sigma) probably because of small polaron hopping between Fe2+ and Fe3+.