Structural microinhomogeneity of fluorophosphate glasses with small additions of europium

The structural microinhomogeneity of EuF3 doped fluorophosphate glasses is studied to elucidate the influence of the Eu3+ ion environment on Rayleigh scattering. The measurements of Rayleigh and Mandelstam-Brillouin scattering, small-angle x-ray scattering, y-ray induced optical absorption, and fluorescence are used. It is shown that the introduction of Eu3+ ions into fluorophosphate glass with a small amount of phosphate decreases the Landau-Placzek ratio. Based on the analysis of the optical absorption and x-ray scattering spectra, the grouping of the Eu3+ ions with the phosphate groups is demonstrated. Applying the capture volume model, the maximum concentration of the Eu3+ ions in the phosphate environment is estimated to be 1.05x1018cm-3. It is found that the capture volumes of the Eu3+ located in the phosphate and mixed environment differ by two orders of magnitude, which approves the discussion in terms of the doped ion segregation.