2014/05/24 by Yukari Fujioka, Johannes Frantti, Fujioka, Yukari +8
Materials Science · Physics and Astronomy · #Magnetic Properties and Synthesis of Ferrites #Multiferroics and related materials #X-ray Diffraction in Crystallography #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.1405.6330
12 pages, 4 color figures, 3 tables
arxiv created 2014/05/24 · arxiv updated 2014/05/27
Forming a solid-solution of NiTiO3 and CoTiO3, two isostructural (ilmenite) and isosymmetrical (space group R-3) compounds, result in a single-phase compound with a remarkably low crystal symmetry. By neutron and X-ray synchrotron powder diffraction techniques, the space group symmetry of the Ni0.6Co0.4TiO3 sample was found to be triclinic P-1 at room temperature, far above the magnetic transition temperature. Ni and Co ions were found to prefer positions close to the octahedron center, whereas Ti ions took off-center positions. This structural distortion is the first known case in ilmenites and opens up ways to modify functional properties of magnetic oxides. Origin of the symmetry lowering is discussed.