Crystal and magnetic study of the disordered perovskites Ca(Mn{sub 0.5}Sb{sub 0.5})O{sub 3} and Ca(Fe{sub 0.5}Sb{sub 0.5})O{sub 3}
Journal Article
·
· Materials Research Bulletin
- Instituto de Ciencia de Materiales de Madrid, CSIC, Energia, Medio Ambiente y Tecnologias Sostenibles, Sor Juana Ines de la Cruz 3, Cantoblanco, E-28049 Madrid (Spain)
- Departamento de Fisica Aplicada, EPS, Universidad Carlos III, Avda. Universidad 30, E-28911 Leganes-Madrid (Spain)
- Institut Max Von Laue Paul Langevin, F-38042 Grenoble (France)
We have investigated the double perovskites Ca{sub 2}MSbO{sub 6} (M = Mn, Fe) that have been prepared by solid-state reaction (M = Fe) and wet chemistry procedures (M = Mn). The crystal and magnetic structures have been studied from X-ray (XRD) and neutron powder diffraction (NPD) data. Rietveld refinements show that the crystal structures are orthorhombic (space group Pbnm) with complete disorder of M and Sb cations, so the formula should be rewritten as Ca(M{sub 0.5}Sb{sub 0.5})O{sub 3}. Due to this disorder no evidences of Jahn-Teller distortion can be observed in the MnO{sub 6} octahedra of Ca(Mn{sub 0.5}Sb{sub 0.5})O{sub 3}, in contrast with the ordered double perovskite Sr{sub 2}MnSbO{sub 6}. Ca(Fe{sub 0.5}Sb{sub 0.5})O{sub 3} behaves as an antiferromagnet with an ordered magnetic moment for Fe{sup 3+} of 1.53(4){mu}{sub B} and a propagation vector k = 0, as investigated by low-temperature NPD. The antiferromagnetic ordering is a result of the high degree of Fe/Sb anti-site disorder of the sample, which originates the spontaneous formation of Fe-rich islands, characterized by the presence of strong Fe-O-Fe antiferromagnetic couplings with enough long-range coherence to produce a magnetic contribution perceptible by NPD. By contrast, the magnetic structure of Ca(Mn{sub 0.5}Sb{sub 0.5})O{sub 3} cannot be observed by low-temperature NPD because the magnitude of the ordered magnetic moments is below the detection threshold for neutrons.
- OSTI ID:
- 22202830
- Journal Information:
- Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 10 Vol. 45; ISSN MRBUAC; ISSN 0025-5408
- Country of Publication:
- United States
- Language:
- English
Similar Records
Preparation, structural study from neutron diffraction data and magnetism of the disordered perovskite Ca(Cr{sub 0.5}Mo{sub 0.5})O{sub 3}
Synthesis, structure and magnetic properties of A{sub 2}MnB'O{sub 6} (A=Ca, Sr; B'=Sb, Ta) double perovskites
Structural, magnetic and electrochemical characterization of La{sub 0.83}A{sub 0.17}Fe{sub 0.5}Cr{sub 0.5}O{sub 3-{delta}} (A = Ba, Ca) perovskites
Journal Article
·
Tue Aug 15 00:00:00 EDT 2006
· Journal of Solid State Chemistry
·
OSTI ID:20905402
Synthesis, structure and magnetic properties of A{sub 2}MnB'O{sub 6} (A=Ca, Sr; B'=Sb, Ta) double perovskites
Journal Article
·
Mon Sep 15 00:00:00 EDT 2008
· Journal of Solid State Chemistry
·
OSTI ID:21128450
Structural, magnetic and electrochemical characterization of La{sub 0.83}A{sub 0.17}Fe{sub 0.5}Cr{sub 0.5}O{sub 3-{delta}} (A = Ba, Ca) perovskites
Journal Article
·
Wed Jul 01 00:00:00 EDT 2009
· Materials Research Bulletin
·
OSTI ID:22029798