Structure determination complicated by tetragonal pseudosymmetry
نویسندگان
چکیده
منابع مشابه
Structure determination of A2M3+TaO6 and A2M3+NbO6 ordered perovskites: octahedral tilting and pseudosymmetry.
The room-temperature crystal structures of six A(2)M(3+)M(5+)O(6) ordered perovskites have been determined from neutron and X-ray powder diffraction data. Ba(2)YNbO(6) adopts the aristotype high-symmetry cubic structure (space group Fm\overline 3m, Z = 4). The symmetries of the remaining five compounds were lowered by octahedral tilting distortions. Out-of-phase rotations of the octahedra about...
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La12xSr xCoO3 ~LSCO! has recently been found to exhibit large magnetoresistance ~MR! effect. In this paper, microstructures of LSCO thin films, which may provide important clues for understanding the unusual MR characteristics in these intrinsic magnetic oxides, were determined by transmission electron microscopy. An ordered, anisotropic perovskite-type structure n-LSCO was observed and its ato...
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ژورنال
عنوان ژورنال: Acta Crystallographica Section A Foundations of Crystallography
سال: 2011
ISSN: 0108-7673
DOI: 10.1107/s0108767311091069