Mechanochemically assisted synthesis of yttrium–lanthanum orthoferrite: Structural and magnetic characterization

A. A. CRISTÓBAL; P. M. BOTTA; P.G. BERCOFF; E. F. AGLIETTI; H. R. BERTORELLO; J. M. PORTO LÓPEZ

JOURNAL OF ALLOYS AND COMPOUNDS

Elsevier

Año: 2010 p. 516 - 519

0925-8388

Y0.5La0.5FeO3 polycrystalline powder was synthesized by mechanochemical activation of Fe3O4-La2O3-Y2O3 reactive mixtures. X-ray diffraction was used to follow the evolution of the formation of this orthoferrite. Peaks corresponding to reactants are no longer observed after 3h, suggesting the completion of the reaction at this milling time. Magnetic hysteresis loops measured at room temperature revealed a gradual decrease of saturation magnetization consistent with the consumption of ferrimagnetic Fe3O4 and the formation of antiferromagnetic Y0.5La0.5FeO3. However, a small ferromagnetic contribution was observed even after 3 h of milling, which can be attributed to a canting in the alignment of the two sub-lattices in orthoferrite structure. This uncompensated antiferromagnetism disappeared when the solid was heated, giving rise to a nearly antiferromagnetic structure.