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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 (tp) 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.

X-ray powder diffraction data for a new potassium sodium silicate Na1.3K0.7Si2O5are reported. The sample was prepared by calcining a mixture of NaOH, KOH, and sodium silicate (SiO2/Na2O=3.54, moisture content=60%) at 873 K for 2 h. The crystallographic data obtained by using the whole-powder-pattern decomposition method are Na1.3K0.7Si2O5, monoclinic, P21/c, a=4.8426(1) Å,b= 8.6892(2) Å,c= 11.9686(3) Å,β=90.373(2)°,V=503.60(2) Å3,Z=4,Dx= 2.51 g/cm3.