Comparative Study of Potentially Jeff = 0 Ground State Iridium(V) in SrLaNiIrO6, SrLaMgIrO6, and SrLaZnIrO6.

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]