INFIQC   05475
INSTITUTO DE INVESTIGACIONES EN FISICO- QUIMICA DE CORDOBA
Unidad Ejecutora - UE
artículos
Título:
New ferromagnetic La3Co2TaO9 double perovskite: Structural and magnetic properties
Autor/es:
V.C. FUERTES; M.C. BLANCO; D.G. FRANCO; J.M. DE PAOLI; E.V. PANNUNZIO MINER; R.D. SÁNCHEZ; M.T. FERNÁNDEZ-DÍAZ; R.E. CARBONIO
Revista:
PHYSICA B - CONDENSED MATTER
Editorial:
Elsevier
Referencias:
Año: 2009 vol. 404 p. 2717 - 2719
ISSN:
0921-4526
Resumen:
The new double perovskite La3Co2TaO9 has been prepared by asolid-state procedure. The crystal and magnetic structures have been studied from X-ray powder diffraction (XRPD) and neutron powder diffraction (NPD) ata. Rietveld refinements were performed in the monoclinic space group P21/n.The structure consists of an ordered array of alternating B0 O6 and B00 O6 octahedra sharing corners, tilted  along the three pseudocubic axes according to the Glazer notation abc+. Rietveld refinements show  thatat RT the cell parameters are a ¼ 5.6005(7)A˚ , b ¼ 5.6931(7)A˚ , c ¼ 7.9429(9)A˚ and b ¼ 89.9539(7)1, and there fined crystallographic formula of this ‘‘doubleperovskite’’can be written as La2(Co)2d(Co1/3Ta2/3)2cO6. Magnetization measurements and low-temperature NPD data show that the perovskite is aferromagnet with TC ¼ 72K. At high T it follows theCurie–Weiss law with an effective magnetic moment of 3.82mB per Co ion which is very close to spinonly Co2+ (HS).3Co2TaO9 has been prepared by asolid-state procedure. The crystal and magnetic structures have been studied from X-ray powder diffraction (XRPD) and neutron powder diffraction (NPD) ata. Rietveld refinements were performed in the monoclinic space group P21/n.The structure consists of an ordered array of alternating B0 O6 and B00 O6 octahedra sharing corners, tilted  along the three pseudocubic axes according to the Glazer notation abc+. Rietveld refinements show  thatat RT the cell parameters are a ¼ 5.6005(7)A˚ , b ¼ 5.6931(7)A˚ , c ¼ 7.9429(9)A˚ and b ¼ 89.9539(7)1, and there fined crystallographic formula of this ‘‘doubleperovskite’’can be written as La2(Co)2d(Co1/3Ta2/3)2cO6. Magnetization measurements and low-temperature NPD data show that the perovskite is aferromagnet with TC ¼ 72K. At high T it follows theCurie–Weiss law with an effective magnetic moment of 3.82mB per Co ion which is very close to spinonly Co2+ (HS).