Synthesis and characteristic of a new niobate: Ba₅NaCr_0.5Nb_9.5O₃₀

Abstract

A new niobate crystal was synthesized for the first time in BaO−NaO−Cr₂O₃−Nb₂O₃, ystem by the solid state reaction and the flux method. The new compound was studied by X-ray diffraction, electron probe, X-ray microanalysis, chemical analysis and SEM. The result of X-ray powder diffraction show that Ba₅NaCr_0.5 Nb_9.5O₃₀ belongs to the tetragonal tungsten bronze structure, with space group P₄ bm(100) and lattice parameters a=b=12.4450(2)A, c=3.9931(2)A and Z=1. The X-ray powder diffraction lines of the compound were well indexed.

Keywords

niobate / chromium / tungsten bronze structure

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