EPR, IR and DC conductivity studies of xCuO-(100-x) Bi2O3 glasses

Abstract

Glass system xCuO-(100-x) Bi2O3 in the composition range 30-60 mol% of CuO is prepared by melt-quenching technique. The ESR spectra show no hyperfine splittings in parallel part but the peak to peak field width is found to vary with CuO content. The observed g effective values are found to vary with copper oxide. The absence of hyperfine splittings is due to inhomogeneous broadening. The observed IR spectra suggest the presence of Bi-O bonds. The structure is changing from [BiO6] octahedral to [BiO3] pyramidal units with increasing CuO concentration. D.C. electrical conductivity results indicate that the conduction is electron in nature and arises out of adiabatic hopping of polarons. The activation energy is found to be concentration and temperature dependent.