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Updated: May 28, 2026

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
A new cation- and vacancy-ordered brownmillerite in the Ba-In-Fe-O system revealing hidden order in its cubic
Monica Ceretti1, Gabriel J Cuello2, Denis Sheptyakov3
1ICGM, Univ Montpellier, CNRS, ENSCM, 34000 Montpellier, France. monica.ceretti@umontpellier.fr.
Abstract:
The synthesis and characterization of a previously unreported B-cation ordered Ba2InFeO5 brownmillerite, obtained by an unconventional ultra-high-vacuum method, are reported alongside its cubic perovskite-type counterpart. Neutron diffraction and total scattering studies reveal for both phases ordered oxygen vacancies together with a layered FeO4/InO6 leitmotif, which gives rise to suppressed magnetic susceptibility and low-dimensional magnetic behavior. This work shows that ultra-high vacuum synthesis allows B-cation ordering to get stabilized forming new brownmillerite type oxides, establishing Ba2InFeO5 as a model system for studying isolated 1D-tetrahedral Fe3+ chains, magnetic frustration, and structure-magnetism relationships.
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