Magnetic and X-ray diffraction characterization of stoichiometric Pr2NiO4 and Nd2NiO4 oxides

Article abstract of DOI:10.1016/0038-1098(89)90809-0

We report the crystal structure and the magnetic properties of a new nearly stoichiometric brown phase of Pr₂NiO₄ and Nd₂NiO₄. The Rietveld refinement of the powder X-ray diffraction patterns at room temperature allows us to assign the crystal structure to orthorhombic (Bmab), for both compounds. The magnetic susceptibility data shows antiferromagnetic ordering for temperatures lower than 300K. A noticeable increase appears in the susceptibility around 120K in both oxides, which is associated with the tilt of the NiO₆ octahedra, as has been recently reported in La₂NiO₄.