title: Refinement of crystal structural parameters and charge density using convergent-beam electron diffraction--the rhombohedral phase of LaCrO3.
abstract: Atom positions and anisotropic Debye-Waller factors of the rhombohedral phase of LaCrO(3) have been refined simultaneously with the low-order structure factors, using a structure-analysis method of convergent-beam electron diffraction (CBED) proposed by Tsuda & Tanaka [Acta Cryst. (1999), A55, 939-954]. The method is based on the least-squares fitting between full dynamical calculations and energy-filtered intensities of two-dimensional higher-order Laue-zone (HOLZ) and zeroth-order Laue-zone (ZOLZ) CBED patterns. The positions of the oxygen atoms have been determined with a high precision. Clear anisotropy of the thermal vibrations of the oxygen atoms has been successfully determined by the CBED method for the first time. The charge transfer from the La and Cr atoms to the O atoms has been found from the deformation charge-density map.
authors.affiliation: Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan. k_tsuda@tagen.tohoku.ac.jp
authors.forename: Kenji
authors.initials: K
authors.lastname: Tsuda
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Ogata
authors.forename: Kazunari
authors.initials: K
authors.lastname: Takagi
authors.forename: Takuya
authors.initials: T
authors.lastname: Hashimoto
authors.forename: Michiyoshi
authors.initials: M
authors.lastname: Tanaka