Correlation between refraction basicity and theoretical optical basicity Part I. Alkaline and alkaline-earth silicate glasses

Abstract

Refraction basicity ( B ref) is proposed, which is defined as the ratio of the ionic refraction of oxygen in a silicate glass to that in silica glass. Linear correlations were observed between B ref and the theoretical optical basicity ( Λ th) in alkaline and alkaline-earth silicate glasses, respectively. Some differences were observed between the slopes of lines of these correlations. The difference in the slope suggests that the contribution of symmetry restricted covalency to the reduction of electronic repulsion in cation cannot be reflected on Λ th.