Note on Refractive Index, Atomic Size and Packing in Glasses

JSGT 1931 V15 T041-T053

An attempt has been made to calculate refractive indices of glasses from fundamental considerations. Using values of density given by Peddle, and by English & Turner, the validity of the Lorenz-Lorentz relationwas tested. The calculations assume that the elements in glasses are in the ionic form (cf. Bragg's work on crystalline silicates) and are based on Wasastjerna's values of refractivity. Considering that no allowance for the influence of chemical combination on refractivity has been made, the agreement between observed and calculated values is as good as can be expected (roughly ±0·0100).

J. T. Randall & N. Gee