Local structural change and magnetic dilution effect in (Ca2+, V5+) co-substituted yttrium iron garnet prepared by sol-gel route

Abstract Co-substituted Y 3-2 x Ca 2 x Fe 5- x V x O 12 samples ( x  = 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.95 and 1) were prepared by using citrate sol-gel method. Synchrotron X-ray diffraction (SXRD) measurements combined with Rietveld refinement technique were used to investigate the crystallization, structural parameters and lattice distortion in the samples. Magnetization and Curie temperature were studied by means of a vibrating sample magnetometer (VSM). Molecular-field coefficients N aa , N dd and N ad of the samples were determined by fitting the experimental thermomagnetization curves in the framework of two-sublattice ferrimagnetic model. The information of local structure change was employed to analyze the influence of the substitution effects in the magnetic interactions.