Issue 29, 2020

Piecewise linearity, freedom from self-interaction, and a Coulomb asymptotic potential: three related yet inequivalent properties of the exact density functional

Abstract

The exact energy functional of density functional theory (DFT) is well known to obey various constraints. Three conditions that must be obeyed by the exact energy functional, but may or may not be obeyed by approximate ones, are often pointed out as important in general and for accurate computation of spectroscopic observables in particular. These are: (1) piecewise linearity as a function of the fractional particle number, (2) freedom from one-electron self-interaction, and (3) for a finite system, the functional derivative with respect to the density results in an asymptotic −1/r potential (in Hartree atomic units), where r is the distance from the system center. In this overview, we explain what these conditions are, what they address, and why each one is of importance for spectroscopy. We then show, using specific examples from the literature, that these three properties are related, but are not equivalent and need to be assessed individually.

Graphical abstract: Piecewise linearity, freedom from self-interaction, and a Coulomb asymptotic potential: three related yet inequivalent properties of the exact density functional

Article information

Article type
Perspective
Submitted
11 五月 2020
Accepted
01 七月 2020
First published
01 七月 2020

Phys. Chem. Chem. Phys., 2020,22, 16467-16481

Piecewise linearity, freedom from self-interaction, and a Coulomb asymptotic potential: three related yet inequivalent properties of the exact density functional

L. Kronik and S. Kümmel, Phys. Chem. Chem. Phys., 2020, 22, 16467 DOI: 10.1039/D0CP02564J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements