TY - JOUR A1 - Yusenko, Kirill A1 - Petrushina, M. A1 - Dedova, E. A1 - Portnaygin, A. A1 - Papynov, E. A1 - Filatov, E. A1 - Gubanov, A. T1 - Pressure induced change in the ZrWMoO8 N2 - In this paper we report high-pressure synchrotron x-ray powder diffraction data for the cubic ZrWMoO8. For the first time, extensive structural study of ZrWMoO8 solid solution as a function of pressure was performed. This study shows that disordered cubic-ZrWMoO8 (space group Pa) transforms to ordered cubic-ZrWMoO8 (space group P) at low pressure. A further high-pressure influence leads followed by amorphization of the sample at 2.2 GPa. All transformations are irreversible. Our work will have high impact in the design of new composite materials with well-defined thermal expansion, especially for applications under extreme conditions and high mechanic stress. KW - Phase transition KW - High-pressure KW - Complex oxides PY - 2020 DO - https://doi.org/10.1016/j.matpr.2019.12.141 VL - 25 IS - 3 SP - 428 EP - 430 PB - Elsevier Ltd. AN - OPUS4-50822 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yusenko, Kirill A1 - Petrushina, M. A1 - Dedova, E. A1 - Portnaygin, A. A1 - Papynov, E. A1 - Filatov, E. A1 - Korenev, S. A1 - Gubanov, A. T1 - Effect of temperature and pressure on mixed oxide solid solutions N2 - A hydrothermal synthesis of ZrW2-xMoxO8 (0 ≤ x ≤ 2) from the corresponding precursors is reported in this paper. High-temperature and high-pressure data are presented for the sample with x = 1.6. An increase in temperature initiates the phase transition from tetragonal precursor to orthorhombic-ZrW2-xMoxO8 (x = 1.6) with the subsequent formation of cubic and trigonal phases. The thermolysis parameter of the disordered cubic ZrW2-xMoxO8 (x = 1.6) phase is 803 K, and the coefficient of thermal expansion is α = -4.6∙10–6 K−1. Data on ZrW2-xMoxO8 (x = 1.6) structure as a function of pressure are obtained for the first time. Pressureinduced changes from cubic to orthorhombic ZrW2-xMoxO8 (x = 1.6) phase at 1.38 GPa are observed. The sample amorphization is irreversible during decompression. KW - Phase transition KW - High-pressure KW - Complex oxides PY - 2020 DO - https://doi.org/10.1016/j.inoche.2020.107965 VL - 117 SP - 107965 PB - Elsevier B.V. AN - OPUS4-50821 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yusenko, Kirill A1 - Zvereva, V. A1 - Martynova, S. A1 - Asanov, I. A1 - La Fontaine, C. A1 - Roudenko, O. A1 - Gubanov, A. A1 - Plyusnin, P. A1 - Korenev, S. A1 - Asanova, T. T1 - Insight of the thermal decomposition of ammonium hexahalogenoiridates(IV) and hexachloroiridate(III) N2 - Thermal decomposition of (NH4)3[IrCl6]·H2O, (NH4)2[IrCl6] and (NH4)2[IrBr6] in reductive and inert atmospheres has been investigated in situ using quick-EXAFS and temperature-resolved powder X-ray diffraction. For the first time, (NH4)2[Ir(NH3)Cl5] and (NH4)2[Ir(NH3)Br5] have been proven as intermediates of thermal decomposition of (NH4)3[IrCl6]·H2O, (NH4)2[IrCl6] and (NH4)2[IrBr6]. Thermal degradation of (NH4)2[IrCl6] and (NH4)2[IrBr6] is a more complex process as suggested previously and includes simultaneous formation of (NH4)2[Ir(NH3)Cl5] and (NH4)2[Ir(NH3)Br5] intermediates mixed with metallic iridium. In the inert atmosphere, complexes (NH4)[Ir(NH3)2Cl4] and (NH4)[Ir(NH3)2Br4] as well as [Ir(NH3)3Br3] were proposed as possible intermediates before formation of metallic iridium particles KW - Thermal decomposition KW - Iridium compounds KW - EXAFS KW - In situ PXRD PY - 2020 DO - https://doi.org/10.1039/D0CP02743J VL - 22 IS - 40 SP - 22923 EP - 22934 AN - OPUS4-51224 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -