Physical properties of double perovskite-type barium neodymium osmate Ba2NdOsO6

The crystal, magnetic structures and physical properties of the double perovskite-type barium neodymium osmate Ba2NdOsO6 are investigated through powder X-ray and neutron diffraction, electrical conductivity, magnetic susceptibility, and specific heat measurements. The Rietveld analysis reveals that the Nd and Os ions are arranged with regularity over the six-coordinate B sites in a distorted perovskite ABO3 framework. The monoclinic crystal structure described by space group P21/n (tilt system a−a−c+) becomes more distorted with decreasing temperature from 300 K down to 2.5 K. This compound shows a long-range antiferromagnetic ordering of Os5+ below 65 K. An antiferromagnetic ordering of Nd3+ also occurs at lower temperatures (∼20 K). The magnetic structure is of Type I and the magnetic moments of Nd3+ and Os5+ ions are in the same direction in the ab-plane.