Density Functional Theory for Excited States in a Quasi Local Density Approximation.
Abstract
Density functional theory has been an important method for studying the ground states for systems involving interacting electrons such as atoms, molecules, and solids. This paper helps to extend this theory to excited states. The starting point of this paper is a recent extension of the Hohenberg Kohn Sham (HKS) density functional theory to ensembles of systems consisting of the M lowest eigenstates, equally weighted. As in E(M/xc)(n(r)), and potential, v(M/xc)(r;(n(r'))). The present paper provides expressions for these quantities, valid for systems of slowly varying density. Even for such systems, however, there are essential non-local effects. Nevertheless both E(M/xc) and v(M/xc) can be calculated in terms of quantities characteristic of appropriate uniform thermal ensembles. This theory is the analog of the ground state local density approximation and allows calculation of excited state energies and densities.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 10, 1986
- Accession Number
- ADA164369
Entities
People
- Walter Kohn
Organizations
- University of California, Santa Barbara