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Abstract. A series of polycrystalline double perovskites SrLaBIrO6 (B = Ni, Mg, Zn) containing Ir5+ (5d4) was synthesized by solid state reactions and structural, magnetic and electronic properties were investigated. The isotypic fully ordered double perovskites crystallize in space group P21/n and show semiconducting behavior with estimated bandgaps of approximately 0.2 eV for SrLaNiIrO6 and SrLaZnIrO6, and 0.4 eV for SrLaMgIrO6. SrLaNiIrO6 is an antiferromagnet with a Néel temperature of 74 K (μeff = 3.3 μB, θW = -90 K), whereas SrLaMgIrO6 and SrLaZnIrO6 are weakly paramagnetic. All title compounds exhibit a temperature-independent contribution to the measured magnetic susceptibility, which supports the notion for a van-Vlecktype response originating from the Ir5+ (5d4, Jeff = 0) ions. [ABSTRACT FROM AUTHOR]

Abstract. A series of polycrystalline double perovskites SrLaBIrO6 (B = Ni, Mg, Zn) containing Ir5+ (5d4) was synthesized by solid state reactions and structural, magnetic and electronic properties were investigated. The isotypic fully ordered double perovskites crystallize in space group P21/n and show semiconducting behavior with estimated bandgaps of approximately 0.2 eV for SrLaNiIrO6 and SrLaZnIrO6, and 0.4 eV for SrLaMgIrO6. SrLaNiIrO6 is an antiferromagnet with a Néel temperature of 74 K (μeff = 3.3 μB, θW = -90 K), whereas SrLaMgIrO6 and SrLaZnIrO6 are weakly paramagnetic. All title compounds exhibit a temperature-independent contribution to the measured magnetic susceptibility, which supports the notion for a van-Vlecktype response originating from the Ir5+ (5d4, Jeff = 0) ions. [ABSTRACT FROM AUTHOR]

Low-temperature (200 °C) hydrothermal synthesis of the ruthenium oxides Ca1.5Ru2O7, SrRu2O6, and Ba2Ru3O9(OH) is reported. Ca1.5Ru2O7 is a defective pyrochlore containing RuV/VI; SrRu2O6 is a layered RuV oxide with a PbSb2O6 structure, whilst Ba2Ru3O9(OH) has a previously unreported structure type with orthorhombic symmetry solved from synchrotron X-ray and neutron powder diffraction. SrRu2O6 exhibits unusually high-temperature magnetic order, with antiferromagnetism persisting to at least 500 K, and refinement using room temperature neutron powder diffraction data provides the magnetic structure. All three ruthenates are metastable and readily collapse to mixtures of other oxides upon heating in air at temperatures around 300-500 °C, suggesting they would be difficult, if not impossible, to isolate under conventional high-temperature solid-state synthesis conditions. [ABSTRACT FROM AUTHOR]