Structure study of binary titanophosphate glasses prepared by sol-gel and melting methods

The 70TiO(2) (.) 30P(2)O(5) (mol%) glass was prepared by the sol-gel method. Its structure was examined by means of IR, Raman spectroscopy and X-ray radial distribution function analysis, and was compared with the corresponding melt-derived glass. It was found that average coordination number of Ti4+ ions was almost 6 and Ti4+ ions formed predominantly TiO6 octahedra in the sol-gel-derived glass, while Ti4+ ions were present in the 4, 5 and/or 6-fold coordination states to give average coordination number in-between 4 and 5 in the melt-glass. The preference of high coordination state of Ti4+ ions in the sol-gel glass was consistent with higher refractive index and density than the melt-glass.