V 18 Valence state of atoms in the perovskite-like phase SrxCu3V4O12 (x = 0.67-1.0) and its properties [Text] / V. L. Volkov, N. I. Kadyrova, G. S. Zakharova, M. V. Kuznetsov, N. V. Podval'naya, K. N. Mikhalev, Yu. G. Zainulin // Inorganic Materials. - 2007. - Vol. 43, № 6. - P660-665 : il. - Библиогр. : с. 665 (7 назв.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ПЕРОВСКИТОПОДОБНЫЕ ФАЗЫ -- ФОТОЭЛЕКТРОННАЯ СПЕКТРОСКОПИЯ -- ВАНАДИЙ Аннотация: We report the first synthesis, at high pressure and temperature (p= 6.0–8.0 GPa, t= 1000°C), of SrxCu3V4O12(x= 0.67–1.0), a cation-deficient perovskite-like phase of variable composition (sp. gr.Im, Z= 2). Using x-ray photoelectron spectroscopy, we have determined the binding energies and valence states of atoms in SrxCu3V4O12. The stoichiometric composition of this phase can be represented by the chemical formula Sr2+Cu2+(V2(5+) V2(4+) )O12. Air exposure leads to the formation of SrCO3 and Sr(OH)2 on its surface and to the oxidation of univalent copper and tetravalent vanadium. According to IR spectroscopy data, the penta- and tetravalent vanadium in the high-pressure phase is in octahedral oxygen coordination. The electrical conductivity, magnetic susceptibility, thermal properties, and ion selectivity of this compound have been investigated Полный текст |