Crystal growth, structure and magnetic properties of the double perovskites Ln2MgIrO6 (Ln=Pr, Nd, Sm–Gd)

Single crystals of double-perovskite type lanthanide magnesium iridium oxides, Ln2MgIrO6 (Ln=Pr, Nd, Sm–Gd) have been grown in a molten potassium hydroxide flux. The compounds crystallize in a distorted 1:1 rock salt lattice, space group P21/n, consisting of corner shared MO6 (M=Mg2+ and Ir4+) octahedra, where the rare earth cations occupy the eight-fold coordination sites formed by the corner shared octahedra. Pr2MgIrO6, Nd2MgIrO6, Sm2MgIrO6, and Eu2MgIrO6 order antiferromagnetically around 10–15 K.