English
Related papers

Related papers: Range-separated multideterminant density-functiona…

200 papers

A combined density and first-order reduced-density-matrix (1RDM) functional method is proposed for the calculation of potential energy curves (PECs) of molecular multibond dissociation. Its 1RDM functional part, a pair density functional,…

Chemical Physics · Physics 2020-09-23 Robert van Meer , Oleg Gritsenko , Jeng-Da Chai

We present the theory and implementation of a fully variational wave function -- density functional theory (DFT) hybrid model, which is applicable to many cases of strong correlation. We denote this model the multiconfigurational…

We develop relativistic short-range exchange energy functionals for four-component relativistic range-separated density-functional theory using a Dirac-Coulomb Hamiltonian in the no-pair approximation. We show how to improve the short-range…

Chemical Physics · Physics 2020-06-24 Julien Paquier , Emmanuel Giner , Julien Toulouse

The beryllium dimer and trimer are, despite their small number of electrons, excellent systems for assessing electronic-structure computational methods. With reference data provided by multi-reference averaged coupled-pair functional…

Chemical Physics · Physics 2018-09-25 Peter Reinhardt , Julien Toulouse , Andreas Savin

In this chapter, we provide a review of ground-state Kohn-Sham density-functional theory of electronic systems and some of its extensions, we present exact expressions and constraints for the exchange and correlation density functionals,…

Chemical Physics · Physics 2022-09-12 Julien Toulouse

Accurately describing strong electron correlation in complex systems remains a prominent challenge in computational chemistry as near-term quantum algorithms treating total correlation often require prohibitively deep circuits. Here we…

Computational Engineering, Finance, and Science · Computer Science 2026-04-21 Zhanou Liu , Yuhao Chen , Yingjin Ma , Xiao He , Yuxin Deng

Long-range exchange and correlation effects, responsible for the failure of currently used approximate density functionals in describing van der Waals forces, are taken into account explicitly after a separation of the electron-electron…

Materials Science · Physics 2009-11-11 Janos G. Angyan , Iann C. Gerber , Andreas Savin , Julien Toulouse

We provide a rationale for a new class of double-hybrid approximations introduced by Br\'emond and Adamo [J. Chem. Phys. 135, 024106 (2011)] which combine an exchange-correlation density functional with Hartree-Fock exchange weighted by…

Chemical Physics · Physics 2015-05-30 Julien Toulouse , Kamal Sharkas , Eric Brémond , Carlo Adamo

We extend the range-separated double-hybrid RSH+MP2 method [J. G. Angyan et al., Phys. Rev. A 72, 012510 (2005)], combining long-range HF exchange and MP2 correlation with a short-range density functional, to a fully self-consistent version…

Chemical Physics · Physics 2019-12-24 Szymon Smiga , Ireneusz Grabowski , Mateusz Witkowski , Bastien Mussard , Julien Toulouse

We derive a local approximation for the correlation energy in two-dimensional electronic systems. In the derivation we follow the scheme originally developed by Colle and Salvetti for three dimensions, and consider a Gaussian approximation…

Strongly Correlated Electrons · Physics 2008-11-21 S. Pittalis , E. Rasanen , M. Marques

Based on recent progress on fermionic exchange symmetry we propose a way to develop new functionals for reduced density matrix functional theory. For some settings with an odd number of electrons, by assuming saturation of the inequalities…

Strongly Correlated Electrons · Physics 2018-10-23 Carlos L. Benavides-Riveros , Miguel A. L. Marques

Many chemical systems cannot be described by quantum chemistry methods based on a singlereference wave function. Accurate predictions of energetic and spectroscopic properties require a delicate balance between describing the most important…

Chemical Physics · Physics 2018-06-12 Erik Donovan Hedegård , Julien Toulouse , Hans Jørgen Aagaard Jensen

In order to assess the accuracy of commonly used approximate exchange-correlation density functionals, we present a comparison of accurate exchange and correlation potentials, exchange energy densities and energy components with the…

Condensed Matter · Physics 2007-05-23 Claudia Filippi , Xavier Gonze , C. J. Umrigar

Selecting excitations in localized orbitals to calculate long-range correlation contributions to range-separated density-functional theory can reduce the overall computational effort significantly. Beyond simple selection schemes of excited…

Chemical Physics · Physics 2016-02-29 E Chermak , Peter Reinhardt , Bastien Mussard , Janos Angyan

New density functional theory approach based on a complete active space self-consistent field (CASSCF) reference function in Extended Koopmans' approximation is discussed. Recently, the number of generalizations of density functional theory…

Chemical Physics · Physics 2018-02-15 Sergey Gusarov , Yurii Dmitriev

Range-separated methods combining a short-range density functional with long-range random phase approximations RPAs with or without exchange response kernel are tested on rare-gas dimers and the S22 benchmark set of weakly interacting…

Chemical Physics · Physics 2014-04-10 Wuming Zhu , Julien Toulouse , Andreas Savin , János G. Angyán

We use continuum mechanics [Tao \emph{et al}, PRL{\bf 103},086401] to approximate the dynamic density response of interacting many-electron systems. Thence we develop a numerically efficient exchange-correlation energy functional based on…

Mesoscale and Nanoscale Physics · Physics 2012-08-28 Tim Gould , John F. Dobson

Without the use of any empirical fitting to experimental or high-level ab initio data, we present a double-hybrid density functional approximation for the exchange-correlation energy, combining the exact Hartree-Fock exchange and…

Chemical Physics · Physics 2015-06-04 Jeng-Da Chai , Shan-Ping Mao

We present a density functional scheme for calculating the pair density (PD) by means of the correlated wave function. This scheme is free from both of problems related to PD functional theory, i.e., (a) the need to constrain the…

Strongly Correlated Electrons · Physics 2015-06-25 Masahiko Higuchi , Katsuhiko Higuchi

Multiconfigurational short-range density functional theory (MC-srDFT) rigorously combines ground state wavefunction theory with DFT. Unlike single-reference range-separated hybrid functionals, MC-srDFT has lacked theoretically grounded…

Chemical Physics · Physics 2026-03-05 Michał Hapka , Katarzyna Pernal , Ewa Pastorczak