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Surface magnetism of Rh(001) from LDA+U calculations

N. Stojic·N. Binggeli·M. Altarelli
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Abstract

We report calculations indicating the presence of a surface magnetic moment for Rh(001), motivated by the detection of a finite moment by magnetic linear dichroism experiments. We show that, while the density functional with the local density or generalized gradient approximations (LDA and GGA) for exchange and correlation yields a non-magnetic ground state, the application of the GGA plus on-site Coulomb interaction U method predicts surface magnetism, thus offering a solution to the long-standing discrepancy between experiment and theory. The calculated moment on the outermost Rh atom increases with the strength of the effective on-site parameter Ueff=U-J, for Ueff>=1.2 eV, and is as large as 1.24 mu_B for Ueff=2.5 eV.

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N. Stojic, N. Binggeli, M. Altarelli. 2006-03-06. Surface magnetism of Rh(001) from LDA+U calculations. https://doi.org/10.1103/physrevb.73.100405

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