SPECTROSCOPIC ANALYSIS OF THE STRUCTURE AND PROPERTIES OF ALKALI TELLURITE GLASSES

Structural development of tellurite glasses with the addition of Li2O and Na2O has been studied using infrared, Raman, and X-ray photoelectron spectroscopies. The increase in intensity of the peak at 755 cm-1 in the infrared spectra as compared to the peak at 620 cm-1 suggests the transformation of TeO4 building units to TeO3 pyramids with the addition of alkali oxide. Proposed structural change is further supported by the strong compositional dependence of the 755-cm-1 peak in the Raman spectra as well as by the formation of a shoulder in the O 1s peak of X-ray photoelectron spectra. In contrast to alkali silicate glasses, formation of nonbridging oxygens with the addition of alkali oxide is not observed.