Symmetry-based approach to parametrization of embedded-atom-method interatomic potentials

A new approach to the parametrization of the Embedded Atom Method (EAM) potentials describing interatomic interactions in metal crystals has been presented. The proposed method requires that the EAM model correctly reproduces elementary strain processes resulting from the spectral decomposition of the elasticity tensor. Then, an arbitrary process of small strain of the considered crystal will proceed in accordance with the experiment. The parametrization conditions obtained in this way take a particularly simple form thanks to using crystal symmetry at two levels: continuum and atomistic one. At the first level, the symmetry determines the elementary processes and at the second one – it enables the simplification of the formulated parametrization conditions by applying the orthogonality relationships in the point group of the considered crystal. Under the proposed approach, the parametrization equations have been formulated for cubic crystals. The obtained relationships have been used to examine existing parameterizations of the Rosato–Guillope–Legrand potential for a copper crystal and subsequently to determine the individual set of parameters which gives results more consistent with the experimental data.