Structure of Glasses of the Li2O-K2O-GeO2 System: Raman Spectroscopic Data

Glasses of the three-component Li2O-K2O-GeO2 system are studied by Raman spectroscopy. Spectra are curve-fitted and the main structural units formed in the system are established. Conditions of formation of highly coordinated germanium atoms are determined and non-statistic distribution of network-modifying cations is found. It is shown that lithium for potassium substitution is accompanied by a change of coordination number of germanium, which could cause the destruction of Ge-O-Ge bonds with formation of non-bridging oxygens.