Investigation of single-phase glasses using small-angle X-ray scattering techniques

The study of single-phase glasses by X-ray scattering experiments requires special techniques. Experimental methods and data evaluation procedures aimed at obtaining reliable scattering data in the range of small and intermediate scattering angles are described. These techniques have been applied to the study of the intermediate-range order of silica and phosphate glasses. For commercial silica glasses and for phosphate glasses, the zero-angle scattering was found to be a very suitable parameter to quantify the optical homogeneity. The zero-angle scattering of alkaline-earth metaphosphate glasses was analyzed in terms of the formalism of Bhatia & Thornton [Phys. Rev. B. (1970), 2, 3004-3012]. From the results, conclusions were drawn about the chemical short-range order. In magnesium phosphate glasses, the presence of small clusters of about 1 nm diameter was established.