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Related papers: Integer Discontinuity of Density Functional Theory

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We present an accurate local density-functional for electronic-structure calculations within the density functional theory (DFT). The functional is derived by analyzing the structure of the standard perturbative expansion of the correlation…

Materials Science · Physics 2024-11-28 Mario Benites , Angel Rosado , Efstratios Manousakis

The fundamental gap of an interacting many-electron system is given by the sum of the single-particle Kohn-Sham gap and the derivative discontinuity. The latter can be generated by advanced approximations to the exchange-correlation (XC)…

Strongly Correlated Electrons · Physics 2018-07-16 Maria Hellgren

We present a general multi-component density functional theory in which electrons and nuclei are treated completely quantum mechanically, without the use of a Born-Oppenheimer approximation. The two fundamental quantities in terms of which…

Materials Science · Physics 2007-05-23 Thomas Kreibich , Robert van Leeuwen , E. K. U. Gross

The State--Specific Kohn--Sham Density Functional Theory [arXiv:physics/0506037] is used to derive the Kohn-Sham exchange-correlation potential $\vxc$ and exchange-correlation energy $\Eco$ as explicit functionals of $v_s$ and $\phi_1$,…

Chemical Physics · Physics 2025-01-31 James P. Finley

We present a practical and accurate density functional for the exchange-correlation energy of electrons in two dimensions. The exchange part is based on a recent two-dimensional generalized-gradient approximation derived by considering the…

Strongly Correlated Electrons · Physics 2010-06-30 E. Rasanen , S. Pittalis , J. G. Vilhena , M. A. L. Marques

We have performed self-consistent calculations for first and second row atoms using a variant of density-functional theory, the optimized effective potential method, with an approximation due to Krieger, Li and Iafrate and a…

chem-ph · Physics 2009-10-28 Tobias Grabo , E. K. U. Gross

The derivative discontinuity in the exact exchange-correlation potential of ensemble Density Functional Theory (DFT) is investigated at the specific integer number that corresponds to the maximum number of bound electrons, $J_{max}$. A…

Quantum Physics · Physics 2011-11-09 Daniel L. Whitenack , Yu Zhang , Adam Wasserman

We use the exact strong-interaction limit of the Hohenberg-Kohn energy density functional to construct an approximation for the exchange-correlation term of the Kohn-Sham approach. The resulting exchange-correlation potential is able to…

Strongly Correlated Electrons · Physics 2013-04-05 Francesc Malet , André Mirtschink , Jonas C. Cremon , Stephanie M. Reimann , Paola Gori-Giorgi

The exact interaction energy of a many-electron system is determined by the electron pair density, which is not well-approximated in standard Kohn-Sham density functional models. Here we study the (complicated but well-defined) exact…

Chemical Physics · Physics 2015-08-07 Huajie Chen , Gero Friesecke

Kohn-Sham (KS) density functional theory (DFT) is a very efficient method for calculating various properties of solids as, for instance, the total energy, the electron density, or the electronic band structure. The KS-DFT method leads to…

Materials Science · Physics 2019-09-20 Fabien Tran , Jan Doumont , Leila Kalantari , Ahmad W. Huran , Miguel A. L. Marques , Peter Blaha

An interesting fundamental problem in density-functional theory of electronic structure of matter is to construct the exact Kohn-Sham (KS) potential for a given density. The exact potential can then be used to assess the accuracy of…

Atomic and Molecular Clusters · Physics 2019-05-22 Ashish Kumar , Rabeet Singh , Manoj K. Harbola

We put forward new approach for the development of a non-local density functional by a direct modeling of the shape of exchange-correlation (xc) hole in inhomogeneous systems. The functional is aimed at giving an accurate xc-energy and an…

Other Condensed Matter · Physics 2013-08-05 Klaas J. H. Giesbertz , Robert van Leeuwen , Ulf von Barth

From a simplified version of the mathematical structure of the strong coupling limit of the exact exchange-correlation functional, we construct an approximation for the electronic repulsion energy at physical coupling strength, which is…

Chemical Physics · Physics 2017-05-11 Stefan Vuckovic , Paola Gori-Giorgi

We present accurate optical spectra of semiconductors and insulators within a pure Kohn-Sham time-dependent density-functional approach. In particular, we show that the onset of the absorption is well reproduced when comparing to…

Materials Science · Physics 2020-03-18 Sarah Cavo , J. A. Berger , Pina Romaniello

One of the most important open challenges in modern Kohn-Sham (KS) density-functional theory (DFT) is the correct treatment of fractional electron charges and spins. Approximate exchange-correlation (XC) functionals struggle to do this in a…

Chemical Physics · Physics 2015-12-24 Jonathan Nafziger , Adam Wasserman

We propose approximations which go beyond the local density approximation for the short-range exchange and correlation density functionals appearing in a multi-determinantal extension of the Kohn-Sham scheme. A first approximation consists…

Chemical Physics · Physics 2009-11-10 Julien Toulouse , Francois Colonna , Andreas Savin

Two electrons at the threshold of ionization represent a severe test case for electronic structure theory. A pseudospectral method yields a very accurate density of the two-electron ion with nuclear charge close to the critical value.…

Chemical Physics · Physics 2014-08-12 Paul E. Grabowski , Kieron Burke

In approximate Kohn-Sham density-functional theory, self-interaction manifests itself as the dependence of the energy of an orbital on its fractional occupation. This unphysical behavior translates into qualitative and quantitative errors…

Materials Science · Physics 2010-09-28 Ismaila Dabo , Andrea Ferretti , Nicolas Poilvert , Yanli Li , Nicola Marzari , Matteo Cococcioni

Density Functional Theory (DFT) is one of the most widely used methods for "ab initio" calculations of the structure of atoms, molecules, crystals, surfaces, and their interactions. Unfortunately, the customary introduction to DFT is often…

Physics Education · Physics 2010-12-07 Nathan Argaman , Guy Makov

The derivative discontinuity of the exchange-correlation (xc) energy at integer particle number is a property of the exact, unknown xc functional of density functional theory (DFT) which is absent in many popular local and semilocal…

Strongly Correlated Electrons · Physics 2015-06-11 Gao Xianlong , A-Hai Chen , I. V. Tokatly , S. Kurth