The crystallographic and magnetic structure of Ni2O3H

A nickel oxide hydroxide, nominally Ni2O3H, has been synthesized using hydrothermal techniques. The crystallographic and magnetic structures of the material have been determined at 4.5 K from powder neutron diffraction data. The material, which is nonstoichiometric with respect to Ni and H, contains Ni2+ and Ni4+ rather than Ni3+ and is orthorhombic (space group Pnmn; a = 5.084(1) Å, b = 2.9103(6) Å, c = 13.954(3) Å). Magnetic moments are aligned along the c axis with antiferromagnetic order. Powder neutron diffraction data collected above the Néel temperature, at 298 and 473 K, revealed no significant changes to the structure or localized electron model.