title: X-ray powder diffraction beamline at D10B of LNLS: application to the Ba2FeReO6 double perovskite.
abstract: A new beamline, fully dedicated to X-ray powder diffraction (XPD) measurements, has been installed after the exit port B of the bending magnet D10 at the Brazilian Synchrotron Light Laboratory (LNLS) and commissioned. The technical characteristics of the beamline are described and some performance indicators are listed, such as the incoming photon flux and the angular/energy resolutions obtainable under typical experimental conditions. The results of a Rietveld refinement for a standard sample of Y2O3 using high-resolution data are shown. The refined parameters match those found in the literature, within experimental error. High-resolution XPD measurements on Ba2FeReO6 demonstrate a slight departure from the ideal cubic double-perovskite structure at low temperatures, not detected by previous powder diffraction experiments. The onset of the structural transition coincides with the ferrimagnetic ordering temperature, Tc approximately equal to 315 K. Subtle structural features, such as those reported here for Ba2FeReO6, as well as the determination and/or refinement of complex crystal structures in polycrystalline samples are ideal candidate problems to be investigated on this beamline.
authors.affiliation: Laboratório Nacional de Luz Síncrotron, Caixa Postal 6192, CEP 13084-971, Campinas, SP, Brazil.
authors.forename: Fabio Furlan
authors.initials: FF
authors.lastname: Ferreira
authors.forename: Eduardo
authors.initials: E
authors.lastname: Granado
authors.forename: Wilson
authors.initials: W
authors.lastname: Carvalho
authors.forename: Stefan W
authors.initials: SW
authors.lastname: Kycia
authors.forename: Daniele
authors.initials: D
authors.lastname: Bruno
authors.forename: Roosevelt
authors.initials: R
authors.lastname: Droppa
mesh_terms: D001938:Brazil; D017610:Calcium Compounds / Q000032:analysis* / Q000737:chemistry*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008968:Molecular Conformation; D010087:Oxides / Q000032:analysis* / Q000737:chemistry*; D033362:Powder Diffraction / Q000295:instrumentation* / Q000379:methods; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods; D017356:Synchrotrons / Q000295:instrumentation*; D014025:Titanium / Q000032:analysis* / Q000737:chemistry*; D014961:X-Ray Diffraction / Q000295:instrumentation* / Q000379:methods
chemical_list: D017610:Calcium Compounds; D010087:Oxides; C059910:perovskite; D014025:Titanium