E.M Sosa-Hernández^a y P.G. Alvarado–Leyva* ^b

^a Departamento de Matemáticas Aplicadas, Facultad de Contaduría y Administración Universidad Autónoma de San Luis Potosí Álvaro Obregón 64, 78000 San Luis Potosí, S.L.P. México

^b Departamento de Física, Facultad de Ciencias Universidad Autónoma de San Luis PotosíÁlvaro Obregón 64, 78000 San Luis Potosí, S.L.P. México

Recibido: 28 de agosto de 2008;
Aceptado: 2 de diciembre de 2008

Abstract

We have studied the optimum geometries and the magnetic behavior of small binary Co_nSi_m (n + m ≤ 4) clusters using abinitio spin-polarized density functional calculations. Our results reveal, the optimized clusters present magnetic behavior and depends of the number of Si atoms in the cluster, in some cases the local magnetic moments at Co atoms present an enhancement respect to Co bulk magnetization, whereas the Si atoms present local magnetic moments whose modulus take significative values. All the clusters studied here present a charge transference to Si atoms from Co atoms, giving polar characteristics to the clusters.

Keywords: Hibridizations, Charge transference, Local magnetic moments.

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