Structure and magnetic properties of Sr2CoRuO6

X-ray, neutron diffraction, magnetization, and resistivity measurements have been carried out on polycrystalline Sr2CoRuO6. It crystallizes with monoclinic cell in I2/c space group. In this structure Co and Ru are randomly distributed. AC magnetic susceptibility and dc magnetization exhibits a cusp and bifurcation of the ZFC and FC magnetization at the spin glass transition temperature ∼95 K as against the expected ferromagnetic ordering due to Co3+ (t2g4 eg2)-O-Ru5+ (t2g3 eg0) interaction. The absence of enhancement in the intensity of the fundamental reflections and superlattice reflection in the neutron diffraction together with absence of neutron depolarization establishes that this compound lacks long range magnetic ordering and is a spin glass. A weak magnetoelastic coupling is observed in the form of an anomaly at the TSG in the temperature variation of bond lengths and angles. Resistivity measurement shows that Sr2CoRuO6 is a semiconductor with 3D Mott type VRH conduction mechanism.