3D to 2D Magnetic Ordering of Fe3+ Oxides Induced by Their Layered Perovskite Structure

Xabier Martínez de Irujo-Labalde; Ulises Amador; Clemens Ritter; Masato Goto; Midori Amano Patino; Yuichi Shimakawa; Susana García-Martín

doi:10.1021/acs.inorgchem.1c00529

3D to 2D Magnetic Ordering of Fe³⁺ Oxides Induced by Their Layered Perovskite Structure

Inorg Chem. 2021 Jun 7;60(11):8027-8034. doi: 10.1021/acs.inorgchem.1c00529. Epub 2021 May 19.

Authors

Xabier Martínez de Irujo-Labalde^{1

2}, Ulises Amador³, Clemens Ritter⁴, Masato Goto⁵, Midori Amano Patino⁵, Yuichi Shimakawa⁵, Susana García-Martín¹

Affiliations

¹ Departamento de Química Inorgánica I, Facultad de Ciencias Químicas, Universidad Complutense, 28040 Madrid, Spain.
² Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom.
³ Facultad de Farmacia, Departamento de Química y Bioquímica, Urbanización Montepríncipe, Boadilla del Monte, Universidad San Pablo-CEU, CEU Universities, E-28668 Madrid, Spain.
⁴ Institut Laue-Langevin, 6, rue Jules Horowitz, BP 156-38042 Grenoble, Cedex 9, France.
⁵ Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.

Abstract

The antiferromagnetic behavior of Fe³⁺ oxides of composition RE_1.2Ba_1.2Ca_0.6Fe₃O₈, RE_2.2Ba_3.2Ca_2.6Fe₈O₂₁, and REBa₂Ca₂Fe₅O₁₃ (RE = Gd, Tb) is highly influenced by the type of oxygen polyhedron around the Fe³⁺ cations and their ordering, which is coupled with the layered RE/Ba/Ca arrangement within the perovskite-related structure. Determination of the magnetic structures reveals different magnetic moments associated with Fe³⁺ spins in the different oxygen polyhedra (octahedron, tetrahedron, and square pyramid). The structural aspects impact on the strength of the Fe-O-Fe superexchange interactions and, therefore, on the Néel temperature (T_N) of the compounds. The oxides present an interesting transition from three-dimensional (3D) to two-dimensional (2D) magnetic behavior above T_N. The 2D magnetic interactions are stronger within the FeO6 octahedra layers than in the FeO4 tetrahedra layers.