STRUCTURAL STUDY OF LIPO3-TEO2 GLASSES

Short range order of three samples in the mixed glass former system, L iPO3-TeO2, are investigated by X-ray diffraction and FT-Raman spectros copy. The questions addressed in this study concern the effect of the mixed former on the structure in the presence of a modifier. P-O and T e-O distances are in the range reported for other phosphate and tellur ite glasses. Te-Te interaction is the major deformation exhibited by T eO4 polyhedra in their chains. Mixed glass formation in Li2O-P2O5-TeO2 system creates greater stability with higher T-g when compared to bin ary glasses Li2O-P2O5 and Li2O-TeO2. Higher T-g owes its origin to the increased bridging between the PO4 and TeO4 chains. (C) 1997 Elsevier Science B.V.