Quantum-Mechanical Interpretation of the Exchange-Correlation Potential of Kohn-Sham Density-Functional Theory

Abstract

We interpret the exchange-correlation potential of Kohn-Sham density-functional theory to be the work required to move an electron against the electric field of its Fermi-Coulomb hole charge distribution. We substantiate this interpretation in the exchange-only approximation by proving the satisfaction of a necessary condition as well as by application to few-electron atomic and many-electron metallic surface systems. This interpretation also provides insights into the exact Slater exchange potential.