Nonlocal potentials in independent-electron models

TL;DR

This paper discusses extending density-functional theory with nonlocal potentials, proposing practical methods, and emphasizing the importance of a parametrized correlation energy functional for accurate many-electron modeling.

Contribution

It introduces a practical methodology for including nonlocal one-electron potentials in density-functional theory, based on orbital functional theory.

Findings

Theoretical model is exact in principle for N-electron systems.

Practical implementation relies on a parametrized correlation energy functional.

Highlights the historical context and ongoing development in the field.

Abstract

This note summarizes the motivation for extending current density-functional theory to include nonlocal one-electron potentials, and proposes methodology for practical calculations. The theoretical model, orbital functional theory, has been shown to be exact in principle for the general N-electron problem, but must depend in practice on a parametrized correlation energy functional. The discussion here is intended to honor Lee Allen and to bring up to date some conversations that we began in 1954.