Structural organization and thermal properties of the Sb₂O₃–SbPO₄glass system

Abstract

The structural organization of Sb2O3–SbPO4 glasses has been studied by FTIR, Raman, 31P MAS and spin echo NMR, Mössbauer and X-ray absorption spectroscopy (EXAFS and XANES at K and L3,1–Sb edges). The combined results can be explained in terms of two potential mechanisms describing the change of the Sb(III) local environment upon incorporation of Q(4)-type phosphate. The formation of the latter species requires anionic compensation that may be adjusted by (a) formation of non bridging oxygen or (b) formation of SbO4E− groups (E = non-bonding electron pair). The second model is favored.