Approach to thermal properties and electronic polarizability from average single bond strength in ZnOBi 2O 3B 2O 3 glasses

Abstract

The glass transition temperature ( T g), density, refractive index, Raman scattering spectra, and X-ray photoelectron spectra (XPS) for xZnO– yBi 2O 3– zB 2O 3 glasses ( x=10–65, y=10–50, z=25–60 mol%) are measured to clarify the bonding and structure features of the glasses with large amounts of ZnO. The average electronic polarizability of oxide ions ( α O2−) and optical basicity ( Λ) of the glasses estimated using Lorentz–Lorenz equation increase with increasing ZnO or Bi 2O 3 content, giving the values of α O2−=1.963 Å 3 and Λ=0.819 for 60ZnO–10Bi 2O 3–30B 2O 3 glass. The formation of BOBi and BOZn bridging bonds in the glass structure is suggested from Raman and XPS spectra. The average single bond strength ( B MO ) proposed by Dimitrov and Komatsu is applied to the glasses and is calculated using single bond strengths of 150.6 kJ/mol for ZnO bonds in ZnO 4 groups, 102.5 kJ/mol for BiO bonds in BiO 6 groups, 498 kJ/mol for BO bonds in BO 3 groups, and 373 kJ/mol for BO bonds in BO 4 groups. Good correlations are observed between T g and B MO , Λ and B MO , and T g and Λ, proposing that the average single bond strength is a good parameter for understanding thermal and optical properties of ZnOBi 2O 3B 2O 3 glasses.