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Related papers: Approximations to the exact exchange potential: KL…

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Capturing the discontinuous shift by $\Delta$ in the exact exchange-correlation (xc) potential is the standard proposal for calculating the fundamental gap, $E_\mathrm{g}$, from the Kohn-Sham (KS) gap, $\varepsilon_\mathrm{g}$, within KS…

Materials Science · Physics 2021-01-14 M. J. P. Hodgson , J. Wetherell , Emmanuel Fromager

We identify peak and valley structures in the exact exchange-correlation potential of time-dependent density functional theory that are crucial for time-resolved electron scattering in a model one-dimensional system. These structures are…

Chemical Physics · Physics 2018-01-03 Yasumitsu Suzuki , Lionel Lacombe , Kazuyuki Watanabe , Neepa T. Maitra

The optimized effective potential (OEP) is the exact Kohn-Sham potential for explicitly orbital-dependent energy functionals, e.g., the exact exchange energy. We give a proof for the OEP equation which does not depend on the chain rule for…

Materials Science · Physics 2009-11-10 Stephan Kümmel , John P. Perdew

We calculate the exact Kohn-Sham (KS) scalar and vector potentials that reproduce, within current-density functional theory, the steady-state density and current density corresponding to an electron quasiparticle added to the ground state…

Mesoscale and Nanoscale Physics · Physics 2015-06-17 J. D. Ramsden , R. W. Godby

The reconstruction of the exchange-correlation potential from accurate ab initio electron densities can provide insights into the limitations of the currently available approximate functionals and provide guidance for devising improved…

Strongly Correlated Electrons · Physics 2013-02-05 Katharina Boguslawski , Christoph R. Jacob , Markus Reiher

In our previous study [Phys. Rev. B 86, 201104 (2012)] we introduced the so called quasi-non-uniform gradient-level exchange-correlation approximation (QNA) and demonstrated it's strength in producing highly accurate equilibrium volumes for…

Materials Science · Physics 2015-06-18 H. Levämäki , L. Vitos , M. P. J. Punkkinen , K. Kokko

This work presents an alternative, general, and in-principle exact extension of electronic Kohn-Sham density functional theory (KS-DFT) to the fully quantum-mechanical molecular problem. Unlike in existing multi-component or…

Chemical Physics · Physics 2024-05-14 Emmanuel Fromager , Benjamin Lasorne

We present analytic expressions for the exact density functional and Kohn-Sham Hamiltonian of simple tight-binding models of correlated electrons. These are the single- and double-site versions of the Anderson, Hubbard and spinless fermion…

Strongly Correlated Electrons · Physics 2012-01-16 D. J. Carrascal , J. Ferrer

The exchange-correlation potential experienced by an electron in the free space adjacent to a solid surface or to a low-dimensional system defines the fundamental image states and is generally important in surface- and nano-science. Here we…

Mesoscale and Nanoscale Physics · Physics 2016-06-01 V. U. Nazarov

Quantum rings can be characterized by a specific radius and ring width. For this rich class of physical systems, an accurate approximation for the exchange-hole potential and thus for the exchange energy is derived from first principles.…

Strongly Correlated Electrons · Physics 2009-02-04 E. Rasanen , S. Pittalis , C. R. Proetto , E. K. U. Gross

For properties of interacting electron systems, Kohn-Sham (KS) theory is often favored over many-body perturbation theory (MBPT) owing to its low computational cost. However, the exact KS potential can be challenging to approximate, for…

Materials Science · Physics 2021-01-15 Jack Wetherell , Matthew Hodgson , Leopold Talirz , Rex Godby

Density functionals with a range-separated treatment of the exchange energy are known to improve upon their semilocal forerunners and fixed-fraction hybrids. The conversion of a given semilocal functional into its short-range analog is not…

Chemical Physics · Physics 2019-09-09 Dimitri N. Laikov

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

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 train a neural network as the universal exchange-correlation functional of density-functional theory that simultaneously reproduces both the exact exchange-correlation energy and potential. This functional is extremely non-local, but…

Computational Physics · Physics 2019-10-10 Jonathan Schmidt , Carlos L. Benavides-Riveros , Miguel A. L. Marques

Aiming to combine density functional theory (DFT) and wavefunction theory, we study a mapping from the many-body interacting system to an effectively-interacting Kohn-Sham system instead of a non-interacting Kohn-Sham system. Because a…

Chemical Physics · Physics 2020-02-19 Shunsuke A. Sato , Angel Rubio

We propose a practical approximation to the exchange-correlation functional of (time-dependent) density functional theory for many-electron systems coupled to photons. The (time non-local) optimized effective potential (OEP) equation for…

Mesoscale and Nanoscale Physics · Physics 2015-09-02 Camilla Pellegrini , Johannes Flick , Ilya V. Tokatly , Heiko Appel , Angel Rubio

One of the most powerful strategies to address properties of real many-body systems is to incorporate data obtained for models, for example, to use data of the homogeneous electron gas in order to build the Local Density Approximation for…

Materials Science · Physics 2026-05-05 Muhammed Hüseyin Güneş , Ayoub Aouina , Vitaly Gorelov , Matteo Gatti , Lucia Reining

We propose the no-recoil approximation, which is valid for heavy systems, for a double folding nucleus-nucleus potential. With this approximation, the non-local knock-on exchange contribution becomes a local form. We discuss the…

Nuclear Theory · Physics 2009-11-11 K. Hagino , T. Takehi , N. Takigawa

There are several approximations to the exchange-correlation functional in density-functional theory that accurately predict total energy-related properties of many-electron systems, such as binding energies, bond lengths, and crystal…

Chemical Physics · Physics 2015-09-30 Eli Kraisler , Tobias Schmidt , Stephan Kümmel , Leeor Kronik
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