Magnetic Structure and Electronic Study of Complex Oxygen-Deficient Manganites

✍ Scribed by Raquel Cortés-Gil; María Hernando; M. Luisa Ruiz-González; Eva Céspedes; Carlos Prieto; José M. Alonso; María Vallet-Regí; Antonio Hernando; José M. González-Calbet

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 458 KB
• Volume: 14
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/chem.200800723

✦ Synopsis

Abstract

Neutron diffraction and X‐ray absorption near‐edge structure (XANES) studies have been performed in La~0.5~Ca~0.5~MnO~2.5~, La~0.5~Sr~0.5~MnO~2.5~ and Nd~0.5~Sr~0.5~MnO~2.5~ oxygen‐deficient perovskite compounds obtained by topotactic reduction. They all exhibit a brownmillerite structure with G‐type antiferromagnetic ordering. Mn^2+^, Mn^3+^ and Mn^4+^ coexist at the octahedral sites, whereas only Mn^2+^ is placed in the tetrahedral positions. A magnetic moment of 1.6 μ~B~ has been detected at the tetrahedral layers, which can be explained by assuming Mn^2+^ is in a low‐spin configuration.