ELECTRICAL-PROPERTIES AND INFRARED-SPECTRA OF TEO2FE2O3 GLASSES

The d.c, and a.c. electrical properties on TeO2-Fe2O3 glasses with various compositions of PbO, B2O3 and SiO2 were studied over a frequency range of 10(2)-10(5) Hz and in the temperature range 300-500 K. The a.c, conductivity is proportional to w(n), and the conduction mechanism is due to an electronic hopping process. The effects of composition and temperature on the dielectric constant and loss factor (tan delta) were studied. The infrared absorption spectra of these glasses reveal that the addition of PbO, B2O3 and SiO2 of these glasses does not introduce any new absorption band in the infrared spectrum of TeO2-Fe2O3 glasses. These results prove the distribution of TeO4 polyhedra which determines the network and basic oscillation of the building units in the tellurite glasses.