A variational density-functional calculation of the total atomic binding energy with recently proposed kinetic-energy and exchange-energy functionals

Abstract

Recently, DePristo and Kress have presented a Padé-approximation formula for the kinetic-energy functional of an atom. Also recently, using the DePristo–Kress results, Cedillo, Robles, and Gázquez obtained a Padé-approximation formula for the exchange-energy functional of such a system. These functionals have been adopted in the present work in a variational density-functional calculation of the total atomic binding energy, using the Ne atom as an example. The total-energy functional used in the present work contains the kinetic-energy functional, the functional describing the interaction of the electrons with the atomic nucleus, the functional describing the classical or direct part of the interaction among the electrons, and the exchange-energy functional. The electron (number) density of the Ne atom is modeled by using hydrogenlike one-electron wave functions (with the 2s function orthogonalized to the 1s function) containing three variational parameters. It is found that the DePristo–Kress Padé-approximation formula for the kinetic-energy functional together with the Cedillo–Robles–Gázquez Padé-approximation formula for the exchange-energy functional leads to a total-energy value that is in good agreement with the single-ζ Hartree–Fock total-energy value for the Ne atom.