Nonlocality of Kohn-Sham Exchange-Correlation Fields in Dielectrics

Nonlocality of Kohn-Sham Exchange-Correlation Fields in Dielectrics

The theory of the macroscopic field appearing in the Kohn-Sham exchange-correlation potential for dielectric materials, as introduced by Gonze, Ghosez, and Godby [Phys. Rev. Lett. 78, 294 (1997)], is reexamined. It is shown that this Kohn-Sham field cannot be determined from a knowledge of the local state of the material (local crystal potential, electric field, and polarization) alone. Instead...

Exchange methods in Kohn-Sham theory.

Differences between exchange methods in exchange-only Kohn-Sham theory are highlighted by calculations of diatomic molecule total energies, uncoupled isotropic NMR shieldings, and HOMO-LUMO eigenvalue differences. Optimised effective potential (OEP) and Wu-Yang (WY) results are very similar. Localised Hartree-Fock (LHF) and Krieger-Li-Iafrate (KLI) results are close to one another, but are diff...

Effect of molecular dissociation on the exchange-correlation Kohn-Sham potential.

The effect of molecular dissociation on the exchange-correlation Kohn-Sham potential vxc has been studied by the construction of vxc from the ab initio correlated density r for the monohydrides XH ~X5Li, B! at several bond distances R~X—H!. The molecular dissociation manifests itself in the formation of a characteristic peak of vxc in the bonding region. The partially integrated conditional pro...

Correlation potentials and functionals in Hartree-Fock-Kohn-Sham theory

Kohn-Sham exchange potential for a metallic surface.

The behavior of the surface barrier that forms at the metal-vacuum interface is important for several fields of surface science. Within the density functional theory framework, this surface barrier has two nontrivial components: exchange and correlation. Exact results are provided for the exchange component, for a jellium metal-vacuum interface, in a slab geometry. The Kohn-Sham exact-exchange ...