Nominally pure and activated (Er3+ and Er3++Ce3+) single crystals, grown by using the Czochralski technique from a (Na0.5La0.5)MoO4 melt in various environments and oxidized in air at 100C, were characterized via X-ray diffraction (with lattice parameter and structure refinement using the Rietveld method and single-crystal techniques). The results confirmed that (Na0.5La0.5)MoO4 crystallized in a tetragonal scheelite structure. The crystals (especially unannealed crystals grown in a neutral atmosphere) were shown to contain O vacancies. In addition, some of the samples contained Mo vacancies. The Er3+ distribution over some of the activated crystals was highly heterogeneous. As a result, the crystals contained Er-enriched zones with a distorted scheelite structure.

X-ray Diffraction Study of the Structure and Defect System of Nominally Pure and Er3+- and Ce3+-Activated (Na0.5La0.5)MoO4 Crystals. G.M.Kuzmicheva, E.V.Zharikov, K.A.Subbotin, D.A.Lis, V.B.Rybakov: Inorganic Materials, 2005, 41[9], 998-1009