IFLP   13074
INSTITUTO DE FISICA LA PLATA
Unidad Ejecutora - UE
artículos
Título:
Local structure and magnetic properties of Mn3+-O-Fe3+ superexchange interaction in an oxygen-vacant perovskite: Experimental and theoretical study
Autor/es:
PARDO, HELENA; MARTÍNEZ, JAVIER; ROMERO, MARIANO; MONTENEGRO, BENJAMÍN; MUDARRA NAVARRO, AZUCENA MARISOL; FACCIO, RICARDO; RICHARD, DIEGO; MOMBRÚ, ALVARO W.
Revista:
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2019 vol. 469 p. 224 - 230
ISSN:
0304-8853
Resumen:
In this work we report an experimental and theoretical study on the local structure and magnetic properties of Mn3+?O?Fe3+ superexchange interaction for an oxygen-vacant perovskite PrBaMnFeO5+δ with δ ∼ 0.5. Structural studies were performed by high resolution X-Ray diffraction technique in normal and anomalous scattering, modeled using an orthorhombic biphasic system corresponding to an oxygen-rich and oxygen-poor stoichiometries. Mössbauer spectroscopy showed the presence of two orthorhombic iron sites, one ascribed to a fully octahedral coordination and another, highly distorted, ascribed to a pyramidal coordination, in full agreement with theoretical DFT + U + SO calculations. The samples showed a spin-glass transition at ∼20 K and mainly the presence of Mn3+?O?Fe3+ type-G antiferromagnetic superexchange interactions. However, our theoretical calculations using first principles also suggested that the presence of oxygen vacancies in certain conditions could be possibly promoting local ferromagnetic interactions.