Electronic structure and properties of oxide glasses (II) Basicity measured by copper(II) ion probe in Na 2OP 2O 5, K 2OB 2O 3 and K 2SO 4ZnSO 4 glasses

Abstract

The correlation between the basicity of oxygens measured by the Cu(II) ion probe and the non-bonding electron density on oxygens in alkali borate glasses was considered. The basicity was measured for K 2OB 2O 3, Na 2OP 2O 5 and K 2SO 4ZnSO 4 glasses and categorized into two types, δ and π, according to the symmetry property of the bonding between a Cu(II) ion and oxygen. The π basicity for borate and phosphate glasses showed an abrupt increase in the vicinity of 17 and 50 mol% alkali oxide, respectively. The values of π-type basicity varied with the composition of glass, being larger in the order: sulfate < phosphate ⪅ borate, whereas δ basicity was constant irrespective of the glass composition. Such a change of the basicity with the composition of glass was interpreted in terms of behavior of non-bonding levels of the ligand oxygens in a glass network.