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Related papers: RPA vs. exact shell-model correlation energies

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We formulate an adiabatic connection for the exchange-correlation energy in terms of pairing matrix fluctuation. This connection opens new channels for density functional approximations based on pairing interactions. Even the simplest…

Chemical Physics · Physics 2015-06-16 Helen van Aggelen , Yang Yang , Weitao Yang

We propose a practical method to solve the random-phase approximation (RPA) in the self-consistent Hartree-Fock (HF) and density-functional theory. The method is based on numerical evaluation of the residual interactions utilizing finite…

Nuclear Theory · Physics 2010-11-26 Takashi Nakatsukasa , Tsunenori Inakura , Kazuhiro Yabana

The "ACFD-RPA" correlation energy functional has been widely applied to a variety of systems to successfully predict energy differences, and less successfully predict absolute correlation energies. Here we present a parameter-free…

Atomic Physics · Physics 2015-06-11 Tim Gould

Electronic correlation energies from the random-phase approximation converge slowly with respect to the plane wave basis set size. We study the conditions, under which a short-range local density functional can be used to account for the…

Materials Science · Physics 2023-07-18 Stefan Riemelmoser , Merzuk Kaltak , Georg Kresse

The reconstruction of the neutrino energy is crucial in oscillation experiments that use interactions with nuclei to detect the neutrino. The common reconstruction procedure is based on the kinematics of the final-state lepton. The…

We extend the capabilities of correlation energy functionals based on the adiabatic-connection fluctuation-dissipation theorem by implementing the analytical atomic forces within the random phase approximation (RPA), in the context of plane…

Materials Science · Physics 2026-03-19 Damian Contant , Maria Hellgren

We study the reliability of the constrained random phase approximation (cRPA) method for the calculation of low-energy effective Hamiltonians by considering multi-orbital lattice models with one strongly correlated "target" band and two…

Strongly Correlated Electrons · Physics 2015-07-24 Hiroshi Shinaoka , Matthias Troyer , Philipp Werner

We check the accuracy of the constrained random phase approximation (cRPA) downfolding scheme by considering one-dimensional two- and three-orbital Hubbard models with a target band at the Fermi level and one or two screening bands away…

Strongly Correlated Electrons · Physics 2018-12-31 Carsten Honerkamp , Hiroshi Shinaoka , Fakher F. Assaad , Philipp Werner

Relativistic Continuum Random Phase Approximation (CRPA) is used to investigate collective excitation phenomena in several spherical nuclei along the periodic table. We start from relativistic mean field calculations based on a covariant…

Nuclear Theory · Physics 2011-03-21 J. Daoutidis , P. Ring

We benchmark three standard approximations for the many-body problem -- the Hartree-Fock, projected Hartree-Fock, and random phase approximations -- against full numerical configuration-interaction calculations of the electronic structure…

Atomic Physics · Physics 2012-08-31 Micah D. Schuster , Calvin W. Johnson , Joshua T. Staker

The Random Phase Approximation (RPA) and its variations and extensions are, without any doubt, the most widely used tools to describe Giant Resonances within a microscopic theory. In this chapter, we will start by discussing how RPA comes…

Nuclear Theory · Physics 2022-01-13 Gianluca Colo'

With the aim of constructing an electronic structure approach that systematically goes beyond the GW and random phase approximation (RPA) we introduce a vertex correction based on the exact-exchange (EXX) potential of time-dependent density…

Materials Science · Physics 2018-07-16 Maria Hellgren , Nicola Colonna , Stefano de Gironcoli

Concerning the su(2)-Lipkin model, the calculation of the excitation energy to the 1st excited-state gives rise to the following fact: The two results based on the exact treatment and the conventional random phase approximation (RPA) are in…

Nuclear Theory · Physics 2022-07-27 Y. Tsue , C. Providencia , J. da Providencia , M. Yamamura

A framework for developing new approximate electronic structure methods is presented, in which the correlation energy of a many-electron system in the ground state is computed as in the single-reference second-order many-body perturbation…

Chemical Physics · Physics 2011-06-15 Dimitri Laikov

The effects of ground-state correlations on the magnetic dipole excitations in $^{40}$Ca are studied using an extended random phase approximation (ERPA) derived from the time-dependent density-matrix theory. Comparison is made with other…

Nuclear Theory · Physics 2020-11-25 Mitsuru Tohyama

We discuss a general mean field plus random phase approximation (RPA) for describing composite systems at zero and finite temperature. We analyze in particular its implementation in finite systems invariant under translations, where for…

Quantum Physics · Physics 2011-04-20 Juan Mauricio Matera , Raul Rossignoli , Norma Canosa

The random-phase approximation (RPA) formulated within the adiabatic connection fluctuation-dissipation framework is a powerful approach to compute the ground-state energies and properties of molecules and materials. Its overall…

Chemical Physics · Physics 2025-05-13 Muhammad N. Tahir , Honghui Shang , Xinguo Ren

We discuss a general treatment based on the mean field plus random phase approximation (RPA) for the evaluation of subsystem entropies and negativities in ground states of spin systems. The approach leads to a tractable general method,…

Quantum Physics · Physics 2011-04-21 J. M. Matera , R. Rossignoli , N. Canosa

An exactly solvable model is introduced, which is equivalent to the exact shell-model treatment of protons and neutrons in a single j-shell for Fermi-type excitations. Exact energies, quasiparticle numbers and double beta decay Fermi…

Nuclear Theory · Physics 2007-05-23 Jorge G. Hirsch , Peter O. Hess , Osvaldo Civitarese

The many-body theory of interacting electrons poses an intrinsically difficult problem that requires simplifying assumptions. For the determination of electronic screening properties of the Coulomb interaction, the Random Phase…

Strongly Correlated Electrons · Physics 2021-07-26 Erik G. C. P. van Loon , Malte Rösner , Mikhail I. Katsnelson , Tim O. Wehling
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