A High Energy X-Ray Diffraction Study of the Atomic-Scale Structure of Novel Vitreous Rare Earth Phosphates*

The magneto-optical properties of rare earth phosphate glasses make them good candidates for numerous potential applications including high-energy/high power ($\sim $10$^{15}$ watt) lasers. Because, properties of these materials depend heavily on their atomic structure, a detailed study can facilitate development of additional applications. A series of (Pr$_{2}$O$_{3})_{x}$(P$_{2}$O$_{5})_{1-x}$ glasses where 0.05 $\le x\le $ 0.25 had been characterized by high energy X-ray diffraction. Coordination parameters for nearest coordination neighbors were obtained by Gaussian fitting. The P-O coordination number, $N_{PO}$, and the P-O, O-O, P-P distances were found to be insensitive to the Pr$_{2}$O$_{3}$ content. Coordination numbers $N_{PrO}$ decreased from $\sim $ 8.0 to $\sim $ 7.5 with increasing Pr$_{2}$O$_{3}$ content from 0.12 to 0.23. Pr-O distance did not seem to vary with Pr$_{2}$O$_{3}$ content in the $x$ range that we studied.