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Title: Density perturbation theory

Despite the fundamental importance of electron density in density functional theory, perturbations are still usually dealt with using Hartree-Fock-like orbital equations known as coupled-perturbed Kohn-Sham (CPKS). As an alternative, we develop a perturbation theory that solves for the perturbed density directly, removing the need for CPKS. This replaces CPKS with a true Hohenberg-Kohn density perturbation theory. In CPKS, the perturbed density is found in the basis of products of occupied and virtual orbitals, which becomes ever more over-complete as the size of the orbital basis set increases. In our method, the perturbation to the density is expanded in terms of a series of density basis functions and found directly. It is possible to solve for the density in such a way that it makes the total energy stationary even if the density basis is incomplete.
Authors:
 [1] ;  [2]
  1. NRC Post-Doctoral Fellow, Naval Research Laboratory, Washington, District of Columbia 20375 (United States)
  2. Code 6189, Chemistry Division, Naval Research Laboratory, Washington, District of Columbia 20375 (United States)
Publication Date:
OSTI Identifier:
22493449
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 143; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COUPLING; DENSITY FUNCTIONAL METHOD; ELECTRON DENSITY; EV RANGE; HARTREE-FOCK METHOD; MATHEMATICAL SOLUTIONS; PERTURBATION THEORY