EXAFS study of glasses of the CaO-Ga_2O_3-GeO_2 system

摘要

X-ray absorption spectroscopy (XAS) measurements for Ca_3Ga_2Ge_3O_(12) and Ca_3Ga_2Ge_4O_(14) glasses are presented. In particular, the extended X-ray absorption fine structure (EXAFS) spectra are analysed and local neighbourhood of Ga and Ge atoms is described in detail. The Ge/Ga atoms neighbourhood in considered glasses is compared with the data available for corresponding crystals. Performed comparative crystal-glass structural analysis confirms correlation between crystalline and glassy structures of the Ca_3Ga_2Ge_3O_(12) and Ca_3Ga_2Ge_4O_(14) compounds. Our results provide several new detailed data, and some general suggestions on the CaO-Ga_2O_3-GeO_2 glass structure.