Raman characterizations and structural properties of the binary TeO 2 WO 3 , TeO 2 CdF 2 and ternary TeO 2 CdF 2 WO 3 glasses

The Raman spectroscopy technique was used to characterize the microstructure and the crystallization properties of the as‐cast and heat‐treated binary TeO 2 WO 3 , TeO 2 CdF 2 and ternary TeO 2 CdF 2 WO 3 glasses and glass ceramics. The results were compared with those obtained by using the X‐ray diffraction technique. The effect of the WO 3 and CdF 2 contents on the TeO 2 glass network and the intensity ratios of the deconvoluted Raman peaks were determined. The shifts in the Raman band wavenumbers and the intensity values for each band were investigated. The Raman results indicated that the glasses were mainly formed by the [TeO 4 ] and [TeO 3 ] units. The [TeO 4 ] units convert to [TeO 3 ] units with the addition of WO 3 and CdF 2 into tellurite glasses. All the crystalline phases such as α‐TeO 2 , δ‐TeO 2 and γ‐TeO 2 existing in the TeO 2 WO 3 , TeO 2 CdF 2 and TeO 2 ‐ WO 3 CdF 2 glasses were determined. The transformation of the metastable γ‐TeO 2 phase into stable α‐TeO 2 was observed for the (1 − x )TeO 2 x WO 3 (where x = 0.15, 0.20, 0.25), 0.90Te 2 0.10CdF 2 , the 0.85TeO 2 0.10CdF 2 0.05WO 3 and 0.80TeO 2 0.10CdF 2 0.10WO 3 glasses, and the transformation of the metastable δ‐TeO 2 phase into the stable α‐TeO 2 was also observed for the TeO 2 CdF 2 WO 3 glass system. In addition, an unidentified phase formation, labeled ε, was determined. Copyright © 2009 John Wiley & Sons, Ltd.