Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7914384 | Solid State Sciences | 2018 | 23 Pages |
Abstract
New A2Fe(Mn0.5W0.5)O6 (Aâ¯=â¯Ca, Sr, Ba) double perovskite oxides have been prepared by ceramic techniques. X-ray diffraction (XRD) complemented with neutron powder diffraction (NPD) indicate a structural evolution from monoclinic (space group P21/n) for Aâ¯=â¯Ca to cubic (Fm-3m) for Aâ¯=â¯Sr and finally to hexagonal (P63/mmc) for Aâ¯=â¯Ba as the perovskite tolerance factor increases with the A2+ ionic size. The three oxides present different tilting schemes of the FeO6 and (Mn,W)O6 octahedra. NPD data also show evidence in all cases of a considerable anti-site disordering, involving the partial occupancy of Fe positions by Mn atoms, and vice-versa. Magnetic susceptibility data show magnetic transitions below 50â¯K characterized by a strong irreversibility between ZFC and FC susceptibility curves. The Aâ¯=â¯Ca perovskite shows a G-type magnetic structure, with weak ordered magnetic moments due to the mentioned antisite disordering. Interesting magnetostrictive effects are observed for the Sr perovskite below 10â¯K.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Crisanto A. GarcÃa-Ramos, Sebastián Larrégola, MarÃa Retuerto, MarÃa Teresa Fernández-DÃaz, Kiril Krezhov, José Antonio Alonso,