A New Approach to Deriving Interatomic Many-Body Interactions in Metals |
| Z. Gurskiia,b and J. Krawczykb aInstitute for Condensed Matter Physics, Ukrainian Academy of Sciences, vul. Svientsitskogo 1, 290011, Lviv, Ukraine bOpole University, Oleska 48, 45-052 Opole, Poland |
| Received: January 29, 1998; revised version May 11, 1998; in final form August 3, 1998 |
| Full Text PDF |
| An original method of treating the kinetic and exchange-correlation energies functionals in terms of many particle interactions was developed. It is based on utilizing the local density approximation. The total electron density, extracted from the ab initio band structure calculations, is expressed as a linear superposition of contributions from the individual pseudoions embedded in the uniform background. The explicit expressions for the pair and triplet potentials are presented. The general form for the part of the pair interatomic interactions caused by the kinetic and the exchange-correlation effects is obtained. Relationship between the developing approach and the perturbation theory in pseudopotential is analysed. Unlike the perturbation theory the advanced approach allows one to calculate accurately the so-called reducible contributions to the pair potential arising from the n -particle (n>2) interactions. It corresponds to summing certain series in pseudopotential. Contribution of the electron-nonlocal pseudopotential interactions to the pair interatomic ones is considered within the concept of the fully separable pseudopotentials. |
| DOI: 10.12693/APhysPolA.94.671 PACS numbers: 71.15.Nc, 71.15.Hx, 34.20.Cf |