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

• Published in: Journal of alloys and compounds 2010-04, Vol.495 (2), p.516-519
• Main Authors: Cristóbal, A.A., Botta, P.M., Bercoff, P.G., Aglietti, E.F., Bertorello, H.R., Porto López, J.M.
• Format: Article
• Language: English
• Subjects: Activation; Alloys; Antiferromagnetism; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Diffraction; Evolution; Exact sciences and technology; Ferromagnetism; Filing; Magnetic measurements; Magnetic properties and materials; Magnetic properties of nanostructures; Magnetically ordered materials; Mechanochemical processing; Physics; Saturation (magnetic)
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2009.10.061

Polycrystalline Y 0.5La 0.5FeO 3 powder was synthesized by mechanochemical activation of Fe 3O 4–La 2O 3–Y 2O 3 reactive mixtures. X-ray diffraction was used to follow the evolution of the formation of this orthoferrite. Peaks corresponding to reactants were no longer observed after 3 h of activation, showing the completion of the reaction after this time. Magnetic hysteresis loops measured at room temperature revealed a gradual decrease of saturation magnetization, consistent with the consumption of ferrimagnetic Fe 3O 4 and the formation of antiferromagnetic Y 0.5La 0.5FeO 3. 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 the orthoferrite structure. This uncompensated antiferromagnetism disappeared when the solid was heated, giving rise to a nearly antiferromagnetic structure.