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.

Department(s)

Materials Science and Engineering

Sponsor(s)

Croatia. Ministry of science, education and sports

Keywords and Phrases

DSC; Crystal Phases; Structure; Tellurite Glasses; Raman Spectroscopy

International Standard Serial Number (ISSN)

0011-1643

Document Type

Article - Journal

Document Version

Final Version

File Type

text

Language(s)

English

Rights

© 2008 Croatian Chemical Society, All rights reserved.

Publication Date

01 Dec 2008

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