Artículos de revistas
Synthesis, structural characterization and magnetic properties of the monoclinic ordered double perovskites BaLaMSbO6, with M = Mn, Co and Ni
Fecha
2014-09Registro en:
Synthesis, structural characterization and magnetic properties of the monoclinic ordered double perovskites BaLaMSbO6, with M = Mn, Co and Ni; Elsevier Science Sa; Journal of Alloys and Compounds; 606; 9-2014; 139-148
0925-8388
CONICET Digital
CONICET
Autor
Blanco, Marìa Cecilia
de Paoli, Juan Martin
Ceppi, Sergio Andres
Tirao, German Alfredo
Nassif, Vivian M.
Guimpel, Julio Juan
Carbonio, Raul Ernesto
Resumen
Double perovskites BaLaMnSbO6, BaLaCoSbO6 and BaLaNiSbO6, were synthesized by conventional ceramic method in air, as polycrystalline powders. The Mn and Ni compounds belong to the I 2/m monoclinic space group, while the Co perovskite belongs to the I 4/m tetragonal space group. Effective presence of Mn2+ has been well established by X-ray emission spectroscopy for BaLaMnSbO6, and there is no evidence of Mn3+. BaLaCoSbO6 and BaLaNiSbO6 only show the expected 3D-antiferromagnetic behavior typical of super-superexchange interactions, while BaLaMnSbO6 displays signs of superparamagnetism in the 40–160 K range, which arises from unbalanced antiferromagnetism inside nanoclusters formed by regions which are rich in Mn2+–O2−–Mn2+ paths. Neutron powder diffraction data for BaLaMnSbO6 reveals that at 3 K, only long range order antiferromagnetic arrangement of Mn2+ spins on 2d octahedral sites is obtained.