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

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 (GGA) for exchange and correlation yields a nonmagnetic 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 μB for Ueff =2.5 eV. © 2006 The American Physical Society.