Synthesis, Structure and Magnetic Properties of La3Co2SbO9: A Double Perovskite with Competing Antiferromagnetic and Ferromagnetic Interactions

D.G. FRANCO; V.C. FUERTES; M.C. BLANCO; M.T. FERNÁNDEZ-DÍAZ; R.D. SÁNCHEZ; R.E. CARBONIO

JOURNAL OF SOLID STATE CHEMISTRY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2012 vol. 194 p. 385 - 385

0022-4596

he synthesis,structural characterization, and magnetic properties of La3Co2SbO9 double perovskite arereported.The crystal structure has been refined by X-ray and neutron powder diffraction data in themonoclinic space group P21/n. Co2+ and Sb5+ have the maximum order allowed for the La3Co2SbO9stoichiometry. Rietveld refinements of powder neutron diffraction data show that at room temperature thecell parameters are a=5.6274(2) A, b=5.6842(2) A, c=7.9748(2) A and bet=89.999(3). Magnetizationmeasurements indicate the presence of ferromagnetic correlations with TC=55K attributed to theexchange interactions for non-linear Co2+?O?Sb5+?O?Co2+ paths.The effective magnetic momentobtained experimentally is mexp=4.38 mB (per mol Co2+), between the theoretical one for spin only(3.87 mB) and spin-orbit value (6.63 mB), indicating partially unquenched contribution.The low magnetizationvalue at high magnetic field and low temperature (1 mB/f.u.,5T and 5K) and the difference betweenZFC and FC magnetiz