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All electron and pseudopotential study of the spin polarization of the V (001) surface: LDA versus GGA

R. Robles·J. Izquierdo·A. Vega·L. C. Balbas
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Abstract

The spin-polarization at the V(001) surface has been studied by using different local (LSDA) and semilocal (GGA) approximations to the exchange-correlation potential of DFT within two ab initio methods: the all-electron TB-LMTO-ASA and the pseudopotential LCAO code SIESTA (Spanish Initiative for Electronic Simulations with Thousands of Atoms). A comparative analysis is performed first for the bulk and then for a N-layer V(001) film (7 < N < 15). The LSDA approximation leads to a non magnetic V(001) surface with both theoretical models in agreement (disagreement) with magneto-optical Kerr (electron-capture spectroscopy) experiments. The GGA within the pseudopotential method needs thicker slabs than the LSDA to yield zero moment at the central layer, giving a high surface magnetization (1.70 Bohr magnetons), in contrast with the non magnetic solution obtained by means of the all-electron code.

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R. Robles, J. Izquierdo, A. Vega, L. C. Balbas. 2000-12-05. All electron and pseudopotential study of the spin polarization of the V (001) surface: LDA versus GGA. https://doi.org/10.1103/physrevb.63.172406

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