Original scientific paper

Structural Properties and Crystallization of Sodium Tellurite Glasses

Ana Šantić ; NMR Center, Ruđer Bošković Institute, Zagreb, Croatia
Andrea Moguš-Milanković ; NMR Center, Ruđer Bošković Institute, Zagreb, Croatia
Krešimir Furić ; Molecular Physics Laboratory, Ruđer Bošković Institute, Zagreb, Croatia
Maša Rajić-Linarić ; Laboratory for Thermal Analysis, Brodarski Institute, Zagreb, Croatia
Chandra S. Ray ; Graduate Center for Materials Research, Missouri University of Science and Technology, Rolla, MO, USA
Delbert E. Day ; Graduate Center for Materials Research, Missouri University of Science and Technology, Rolla, MO, USA

Abstract

The structural properties and crystallization behaviour of xNa2O-(100-x)TeO2 (0 <= x <= 33.3,
x-% mole fraction) glasses have been investigated by Raman spectroscopy, X-ray diffraction
(XRD) and differential scanning calorimetry (DSC). The Raman spectra of glasses show systematic
changes in structural units, from TeO4 trigonal bypiramids (tbps) to TeO3 trigonal pyramids
(tps) with increasing Na2O content in glass. These structural changes are result of
Te–eqOax–Te disruption and the formation of non-bridging oxygens (NBOs) in glass network.
When heated at 623 K for 10 h glasses crystallized to different phases: alpha-TeO2, Na2Te4O9 and
a new crystalline phase which is believed to be a polymorph of Na2Te2O5.

Keywords

tellurite glasses; structure; crystal phases; DSC; Raman spectroscopy

Hrčak ID:

31181

URI

https://hrcak.srce.hr/31181

Publication date:

31.12.2008.

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