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Screened Coulomb interactions in metallic alloys: II Screening beyond the single-site and atomic sphere approximations

A. V. Ruban·S. I. Simak·P. A. Korzhavyi·H. L. Skriver
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Abstract

A quantitative description of the configurational part of the total energy of metallic alloys with substantial atomic size difference cannot be achieved in the atomic sphere approximation: It needs to be corrected at least for the multipole moment interactions in the Madelung part of the one-electron potential and energy. In the case of a random alloy such interactions can be accounted for only by lifting the atomic sphere and single-site approximations, in order to include the polarization due to local environment effects. Nevertheless a simple parameterization of the screened Coulomb interactions for the ordinary single-site methods, including the generalized perturbation method, is still possible. We obtained such a parameterization for bulk and surface NiPt alloys, which allows one to obtain quantitatively accurate effective interactions in this system.

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A. V. Ruban, S. I. Simak, P. A. Korzhavyi, H. L. Skriver. 2002-02-21. Screened Coulomb interactions in metallic alloys: II Screening beyond the single-site and atomic sphere approximations. https://doi.org/10.1103/physrevb.66.024202

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