Embedded atom method potentials employing a faithful density representation

Abstract

We present an approach for deriving embedded atom method energy functionals which employs a faithful representation of the valence electron that reproduces ab initio electronic structure calculations. This approach offers the possibility of improved accuracy and versatility over existing methods. Moreover, the approach has a distinct advantage for coupling to more accurate methods in the context of multiscale schemes. The embedding function is based on first breaking down the electronic density to individual atomic contributions and then designing an interatomic function which captures the interaction between the atomic contributions towards formation of the interatomic bonds. We use Al as a prototypical metallic solid to illustrate the application of the method and we employ density functional theory (DFT) to calculate the electronic charge densities and energies for determining the values of fitting parameters. We validate the approach by reproducing adequately experimental data for the cohesive energy, bulk modulus, elastic constants and dynamical properties at finite temperatures, obtained by molecular dynamics simulations.