COMPOSITION AND STRUCTURE OF SOLID SOLUTIONS IN THE Bi2O3-SiO2-O5 SYSTEM WITH THE STRUCTURE SILLENITE
T. I. Mel'nikova, G. M. Kuz'micheva, V. B. Rybakov, N. B. Bolotina, A. B. Dubovskii, A. Cousson
Keywords: sillenite, hydrothermal synthesis, neutron diffraction, X-ray diffraction, composition, defects, dissymmetrization
Pages: 526-532
Abstract
In the Bi2O3-SiO2-O5 system, single crystal solid solutions of the sillenite family of the general composition Bi24(Bi,Si,V)2O40 are obtained by a hydrothermal method and for the first time characterized by neutron and X-ray diffraction analysis. The tetrahedral position is found to contain vanadium ions with different formal charges (V4+ and V5+) responsible for green and orange colors, respectively, of the samples. For the first time, for some sillenites of this system dissymmetrization of the structure (a transition from the I23 space group into P23) is revealed, which is caused by the presence of several atoms in one crystallographic position and also by crystal growth conditions.
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