Eur. Phys. J. D 52, 171-174 (2009)
https://doi.org/10.1140/epjd/e2009-00026-8

Theoretical study of the magnetic moments and anisotropy energy of CoRh nanoparticles

¹ Instituto de Física, Universidad Autónoma de San Luis Potosí, 78000 San Luis Potosí, Mexico
² Université de Toulouse, LPCNO, INSA, 135 avenue de Rangueil, 31077 Toulouse, France
³ Institut für Theoretische Physik, Universität Kassel, 34132 Kassel, Germany

Corresponding author: ^a pastor@uni-kassel.de

Received: 19 September 2008
Published online: 6 February 2009

Abstract

The role of size, structure and chemical order on the magnetic moments and magnetic anisotropy energy (MAE) of CoRh nanoparticles are studied in the framework of a self-consistent real-space tight-binding method. Our results show that a Rh core in a geometry having a large surface/volume ratio and with Co–Rh mixing at the interface is the most likely chemical arrangement. A local analysis reveals that the orbital and spin moments at the Co–Rh interface are largely responsible for the increase of the magnetic moments and magnetic anisotropy. Moreover, the local moments induced at the Rh atoms, which amount to about 20% of the moment per Co atom [ μ_Rh = (0.2–0.3) μ_B] and the orbital moments of Co atoms play a crucial role on the interpretation of experiment. The results are discussed in the context of the interplay between chemical order and magnetic properties.