Volume 224, 2020

Strategies to build functionals of the density, or functionals of Green’s functions: what can we learn?

Abstract

The many-body problem cannot in general be solved exactly, and one of the most prominent approximations is to build perturbation expansions. A huge variety of expansions are possible, which differ by the quantity to be expanded, the expansion variable, the starting point, and ideas of how to re-sum or terminate the series. Although much has been discussed and much has been done, some choices were made for historical reasons, in particular, limited computation or storage capacities. The present work aims to examine the justification for different choices made in different contexts, by comparing the components of functionals based on Green’s functions on the one side, and on the charge density on the other side. Of particular interest will be the question of how to build an optimal starting point for the approximation of non-local quantities, making use of near- or far-sightedness, and daring to consider models beyond the homogeneous electron gas. This will include the use of connector approximations. We will also discuss why it is a good idea to build functionals of the density.

Graphical abstract: Strategies to build functionals of the density, or functionals of Green’s functions: what can we learn?

Associated articles

Article information

Article type
Paper
Submitted
20 May 2020
Accepted
23 Jun 2020
First published
23 Jun 2020

Faraday Discuss., 2020,224, 27-55

Strategies to build functionals of the density, or functionals of Green’s functions: what can we learn?

A. Aouina, M. Gatti and L. Reining, Faraday Discuss., 2020, 224, 27 DOI: 10.1039/D0FD00068J

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