Synthesis and Characterization of the Double Perovskite Y₂MgRuO₆

A new double perovskite compound with nominal composition Y2MgRuO6 is synthesized by the floating zone technique. X-ray diffraction measurements reveal a monoclinic crystal structure with space group P2(1)/n and monoclinic angle beta = 90.178(1)(degrees) as crystallographically expected for a double perovskite. A composition of Y1.880(8)Mg0.953(4)Ru1.047(4)O6-delta is revealed by our single crystal X-ray diffraction measurement. The magnetic susceptibility of this compound does not show indications of magnetic ordering down to the lowest temperature. A Curie-Weiss fit for the paramagnetic part above 300 K yields an effective moment that indicates an S = 1 Ru4+ state. We attribute the occurrence of the S = 1 state and the lack of magnetic order to the presence of the B/B'-site disorder.