A method for determination of ab initio group model potentials, with the intention of describing the effects of a whole molecule or a chemical group within a density functional theory framework, is reported. The one-electron part of the Kohn–Sham equations is modified by incorporation of a Coulomb operator, which accounts for the classical electron interaction arising from the group. Exchange a...

Low-energy electron diffraction (LEED) is considered as elastic electron-atom scattering (EEAS) operating in a target crystal waveguide, where signal carrier wave wavenumber modulated by exchange-correlation (XC) interaction. A potential designed using KKR (Korringa-Kohn-Rostoker) muffin-tin (MT) model built on overlapping MT spheres that implement atoms with double degree of freedom, radius an...

The general usefulness of various local and non-local approximations to the exchange-correlation potential in density functional theory is studied by comparing resulting electron density distributions to essentially exact results for light atoms. The correlation contribution to the electron density in CO and Hz0 is compared with CI results. It is concluded that density functional theory provide...