Structure of K2O-TeO2 glasses

The structure at room temperature and structural change from room temperature to the temperature above melting point (T-m) of K2O-TeO2 glasses were studied by the use of XAFS spectroscopy, high temperature Raman spectroscopy, high-temperature XRD and X-ray RDF (Radial. Distribution Function). XAFS spectroscopy has indicated that K2O-TeO2 glasses consist of both TeO4 trigonal bipyramid (tbp) units and TeO3 trigonal pyramid (Cp) units, and high-temperature Raman results have indicated that TeO4 tbp units convert to TeO3 tp units with the increase of temperature and by the addition of K2O in the K2O-TeO2 glasses. The high-temperature XRD and X-ray RDF results were in good agreement with the results of the high-temperature Raman spectroscopy. Furthermore, the XAFS spectroscopy has shown that potassium ions have a similar local structure in all K2O-TeO2 glasses studied.