title: Chemical analysis at atomic resolution of isolated extended defects in an oxygen-deficient, complex manganese perovskite.
abstract: A general approach to the structural and analytical characterization of complex bulk oxides that exploits the advantage of the atomic spatial resolution and the analytical capability of aberration-corrected microscopy is described. The combined use of imaging and spectroscopic techniques becomes necessary to the complete characterization of the oxygen-deficient colossal magnetoresistant La(0.56)Sr(0.44)MnO(2.5)-related perovskite. In this compound, the formation of isolated (La/Sr)O and MnO rock-salt-type planar defects are identified from atomically resolved High Angle Annular Dark Field (HAADF) images. The location of the oxygen atomic columns from Annular Bright Field (ABF) images indicates edge-sharing MnO6 octahedra in the MnO planes and the study performed by Electron Energy Loss Spectroscopy (EELS) reveals different Mn oxidation states derived from the corner- or edge-sharing MnO6 octahedra environment.
authors.affiliation: Departamento de Química Inorgánica, Facultad de Químicas, Universidad Complutense (UCM), CEI Moncloa, 28040 Madrid (Spain).
authors.forename: M Luisa
authors.initials: ML
authors.lastname: Ruiz-González
authors.forename: Raquel
authors.initials: R
authors.lastname: Cortés-Gil
authors.forename: Almudena
authors.initials: A
authors.lastname: Torres-Pardo
authors.forename: Daniel
authors.initials: D
authors.lastname: González-Merchante
authors.forename: José M
authors.initials: JM
authors.lastname: Alonso
authors.forename: José M
authors.initials: JM
authors.lastname: González-Calbet
keywords: aberration-corrected microscopy; atomic-resolution STEM; colossal magnetoresistant oxides; electron energy loss spectroscopy (EELS); extended defects