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

Polycrystalline Y(0 5)La(0 5)FeO(3) powder was synthesized by mechanochemical activation of Fe(3)O(4)-La(2)O(3)-Y(2)O(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(3)O(4) and the formation of antiferromagnetic Y(0 5)La(0 5)FeO(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 (C) 2009 Elsevier B V. All rights reserved