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The double-perovskite Mn2VSbO6 has been synthesized by solid-state reaction under pressure at 6 GPa and temperature of 1200°C, and its crystal structure has been refined by X-ray powder diffraction date. Mn2VSbO6 crystallizes in monoclinic space group P121/n1 with the following parameters: a =  5.2340 Å (2), b =  5.3932 Å (2), c =  7.6460 Å (3), β =  89.6075° (23), V =  215.826 Å3 (14), Z =  2. It found that V and Sb atoms are completely ordered in 2d and 2c positions of double-perovskite structure, respectively. According to XPS measurements, manganese in this compound is present as Mn2+, while vanadium is V3+. The magnetization date suggests that Mn2VSbO6 transforms to an antiferromagnetic state due to simultaneous ordering of V3+ and Mn2+ magnetic sublattices at low temperature. [ABSTRACT FROM AUTHOR]

Ba7Li1.75Mn3.5O15.75 is a new hexagonal perovskite whose crystal structure has elements typical for the layered hexagonal perovskites and quasi-one-dimensional oxides, hence representing a new polytype. It has been synthesized via a solid-state microwave route. The crystal structure was solved using a combination of X-ray and neutron diffraction data, which show that Ba7Li1.75Mn3.5O15.75 crystallizes in a hexagonal unit cell with parameters a = 5.66274(2) Å and c = 16.7467(1) Å (V = 465.063(4) Å3), with one formula unit, and can be described as columns of face-shared octahedra occupied by Mn4+ and Li+ cations and vacancies along the c axis separated in the ab plane by barium atoms. Every sixth layer, the coordination of Mn5+ and Li+ changes to tetrahedral. Additional local ordering of manganese and lithium atoms among cationic sites leading to the formation of a rhombohedral supercell has been observed by scanning transmission electron microscopy. [ABSTRACT FROM AUTHOR]

Phase equilibria in the system CaO-CoO-Co2O3-MnO-MnO2 at 700–1200°C in air were studied on the basis of published data and proper experiments. No new compounds were found. The results are presented in the form of 13 isothermal sections of the phase diagram. [ABSTRACT FROM AUTHOR]

Phase equilibria in the system CaO-CoO-Co2O3-MnO-MnO2 at 700–1200°C in air were studied on the basis of published data and proper experiments. No new compounds were found. The results are presented in the form of 13 isothermal sections of the phase diagram. [ABSTRACT FROM AUTHOR]

We have studied the magnetic properties of the new compound Er2Mn2/3Re4/3O7 prepared by reacting Er3ReO8, ReO2, MnO, and metallic Re at 1020°C in silica tubes sealed off under vacuum. The compound is shown to have the zirkelite structure with hexagonal cell parameters a = 7.3174(6) Å and c = 17.365(1) Å (sp. gr. P31211, Z = 6). Magnetization data obtained in the range 2–300 K demonstrate that, above ∼150 K, its magnetic susceptibility exhibits Curie-Weiss behavior with an effective magnetic moment of 9.50μB. Dynamic magnetic susceptibility measurements point to spin-glass behavior of this compound at low temperatures. [ABSTRACT FROM AUTHOR]

Attempts of the synthesis in air of complex oxides Sr3RhMnOx and Sr4Rh1.5Mn1.5Ox resulted in revealing formation of a new oxide phase Sr6.3Rh2.35Mn2.35O9 related to quasi-unidimensional family A3 n+3 m A′ n B3 m+ n O9 m+6 n at n = 1 and m = 1. Its structural characteristics and magnetic properties are studied. X-ray data of the obtained phase is indicated on the basis of trigonal cell (spatial group P321) with the parameters: a 9.6239(4) Å; c 1 4.1130(4) Å, c 2 2.4946(2) Å. Manganese and rhodium exist in the compound as the cations Mn4+, Rh3+ and Rh4+, as follows from the data of measuring of magnetic susceptibility in the range 2–300 K. [ABSTRACT FROM AUTHOR]

Attempts of the synthesis in air of complex oxides Sr3RhMnOx and Sr4Rh1.5Mn1.5Ox resulted in revealing formation of a new oxide phase Sr6.3Rh2.35Mn2.35O9 related to quasi-unidimensional family A3 n+3 m A′ n B3 m+ n O9 m+6 n at n = 1 and m = 1. Its structural characteristics and magnetic properties are studied. X-ray data of the obtained phase is indicated on the basis of trigonal cell (spatial group P321) with the parameters: a 9.6239(4) Å; c 1 4.1130(4) Å, c 2 2.4946(2) Å. Manganese and rhodium exist in the compound as the cations Mn4+, Rh3+ and Rh4+, as follows from the data of measuring of magnetic susceptibility in the range 2–300 K. [ABSTRACT FROM AUTHOR]

Phase equilibria in the CaO-CuO-Cu2O-MnO-MnO2 system at 900–1400°C in air were examined on the basis of published and newly obtained data. No new compounds were revealed. The results are presented in the form of 12 isothermal sections of the phase diagram. [ABSTRACT FROM AUTHOR]