Preparation and physical properties of double perovskite Ln2CuRuO6 (Ln = Nd, Sm) compounds

Abstract The structural and magnetic properties are studied for a series of double perovskite compounds Ln2CuRuO6 (Ln = Nd, Sm) synthesized by solid state reaction method. The analysis of structure shows La3+ is replaced by the smaller rare-earth ions Nd3+ and Sm3+, forming in monoclinic P21/n structure, which results in severe deformation of the Cu–O–Ru bond angle. In addition, the decrease of Cu–O–Ru bond angles and the simultaneous enhancement of magnetic interactions lead to higher transition temperature than that of La2CuRuO6. The consistent trends of the antisite defects and the upturn rate of the magnetic curves indicate that the antisite defects may play an important role on the magnetization at low temperature.