title: Co on Fe3O4(001): Towards precise control of surface properties.
abstract: A novel approach to incorporate cobalt atoms into a magnetite single crystal is demonstrated by a combination of x-ray spectro-microscopy, low-energy electron diffraction, and density-functional theory calculations. Co is deposited at room temperature on the reconstructed magnetite (001) surface filling first the subsurface octahedral vacancies and then occupying adatom sites on the surface. Progressive annealing treatments at temperatures up to 733 K diffuse the Co atoms into deeper crystal positions, mainly into octahedral ones with a marked inversion level. The oxidation state, coordination, and magnetic moments of the cobalt atoms are followed from their adsorption to their final incorporation into the bulk, mostly as octahedral Co(2+). This precise control of the near-surface Co atoms location opens up the way to accurately tune the surface physical and magnetic properties of mixed spinel oxides.
authors.affiliation: Instituto de Química Física "Rocasolano," CSIC, Madrid E-28006, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: Gargallo-Caballero
authors.affiliation: Instituto de Química Física "Rocasolano," CSIC, Madrid E-28006, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Martín-García
authors.affiliation: Instituto de Cerámica y Vidrio, CSIC, Madrid E-28049, Spain.
authors.forename: Adrián
authors.initials: A
authors.lastname: Quesada
authors.affiliation: Department of Chemistry, Aarhus University, Langelandsgade 140, Århus DK-8000, Denmark.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Granados-Miralles
authors.affiliation: ALBA Synchrotron, CELLS, Barcelona, E-08290, Spain.
authors.forename: Michael
authors.initials: M
authors.lastname: Foerster
authors.affiliation: ALBA Synchrotron, CELLS, Barcelona, E-08290, Spain.
authors.forename: Lucía
authors.initials: L
authors.lastname: Aballe
authors.affiliation: Institute of Applied Physics, Vienna University of Technology, Vienna A-1040, Austria.
authors.forename: Roland
authors.initials: R
authors.lastname: Bliem
authors.affiliation: Institute of Applied Physics, Vienna University of Technology, Vienna A-1040, Austria.
authors.forename: Gareth S
authors.initials: GS
authors.lastname: Parkinson
authors.affiliation: Institute of Materials Chemistry, Vienna University of Technology, Vienna A-1060, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Blaha
authors.affiliation: Instituto de Química Física "Rocasolano," CSIC, Madrid E-28006, Spain.
authors.forename: José F
authors.initials: JF
authors.lastname: Marco
authors.affiliation: Instituto de Química Física "Rocasolano," CSIC, Madrid E-28006, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: de la Figuera