English
Related papers

Related papers: Ab Initio Derivation of Model Energy Density Funct…

200 papers

Energy-Based Models (EBMs) have proven to be a highly effective approach for modelling densities on finite-dimensional spaces. Their ability to incorporate domain-specific choices and constraints into the structure of the model through…

Machine Learning · Computer Science 2023-02-24 Jen Ning Lim , Sebastian Vollmer , Lorenz Wolf , Andrew Duncan

We introduce an orbital free electron density functional approximation based on alchemical perturbation theory. Given convergent perturbations of a suitable reference system, the accuracy of popular self-consistent Kohn-Sham density…

Chemical Physics · Physics 2020-05-27 Guido Falk von Rudorff , O. Anatole von Lilienfeld

In a recent paper [Phys.~Rev.~A {\bf 89}, 022503 (2014)], the average density approximation (ADA) was implemented to develop a parameter-free, nonlocal kinetic energy functional to be used in the orbital-free density-functional theory of an…

Quantum Gases · Physics 2015-08-25 J. Towers , B. P. van Zyl , W. Kirkby

We present accurate many-body results of the electronic densities in several solid materials, including Si, NaCl, and Cu. These results are obtained using the ab initio auxiliary-field quantum Monte Carlo (AFQMC) method working in a…

Materials Science · Physics 2021-02-24 Siyuan Chen , Mario Motta , Fengjie Ma , Shiwei Zhang

Machine learning is used to approximate density functionals. For the model problem of the kinetic energy of non-interacting fermions in 1d, mean absolute errors below 1 kcal/mol on test densities similar to the training set are reached with…

Computational Physics · Physics 2015-06-03 John C. Snyder , Matthias Rupp , Katja Hansen , Klaus-Robert Müller , Kieron Burke

Using the Green's function formalism, an ab initio theory for band structures of crystals is derived starting from the Hartree-Fock approximation. It is based on the algebraic diagrammatic construction scheme for the self-energy which is…

Other Condensed Matter · Physics 2007-05-23 Christian Buth , Uwe Birkenheuer , Martin Albrecht , Peter Fulde

The t-J model is studied using a novel and rigorous mapping of the Gutzwiller projected electrons, in terms of canonical electrons. The mapping has considerable similarity to the Dyson-Maleev transformation relating spin operators to…

Strongly Correlated Electrons · Physics 2014-02-28 B Sriram Shastry

In the unitary regime, fermions interact strongly via two-body potentials that exhibit a zero range and a (negative) infinite scattering length. The energy density is proportional to the free Fermi gas with a proportionality constant $\xi$.…

Soft Condensed Matter · Physics 2007-05-23 T. Papenbrock

We present extensive new \textit{ab intio} path integral Monte Carlo results for the momentum distribution function $n(\mathbf{k})$ of the uniform electron gas (UEG) in the warm dense matter (WDM) regime over a broad range of densities and…

Computational Physics · Physics 2021-05-26 Tobias Dornheim , Maximilian Böhme , Burkhard Militzer , Jan Vorberger

We present an efficient and systematically convergent approach to all-electron real-time time-dependent density functional theory (TDDFT) calculations using a mixed basis, termed as enriched finite element (EFE) basis. The EFE basis…

Chemical Physics · Physics 2022-10-27 Bikash Kanungo , Nelson D. Rufus , Vikram Gavini

Nuclear Density Functional Theory (DFT) plays a prominent role in the understanding of nuclear structure, being the approach with the widest range of applications. Hohenberg and Kohn theorems warrant the existence of a nuclear Energy…

Nuclear Theory · Physics 2020-03-03 G. Accorto , P. Brandolini , F. Marino , A. Porro , A. Scalesi , G. Colò , X. Roca-Maza , E. Vigezzi

In this work we give a comprehensive derivation of an exact and numerically feasible method to perform ab-initio calculations of quantum particles interacting with a quantized electromagnetic field. We present a hierachy of…

Quantum embedding schemes have the potential to significantly reduce the computational cost of first principles calculations, whilst maintaining accuracy, particularly for calculations of electronic excitations in complex systems. In this…

Materials Science · Physics 2022-03-10 Joseph C. A. Prentice

Ensemble density functional theory (EDFT) is a promising alternative to time-dependent density functional theory for computing electronic excitation energies. Using coordinate scaling, we prove several fundamental exact conditions in EDFT…

Strongly Correlated Electrons · Physics 2023-07-04 Thais R. Scott , John Kozlowski , Steven Crisostomo , Aurora Pribram-Jones , Kieron Burke

Density functional theory underlies the most successful and widely used numerical methods for electronic structure prediction of solids. However, it has the fundamental shortcoming that the universal density functional is unknown. In…

Disordered Systems and Neural Networks · Physics 2020-09-23 M. Michael Denner , Mark H. Fischer , Titus Neupert

We present a method to calculate spectroscopic properties of odd-odd nuclei within the framework of the Interacting Boson-Fermion-Fermion Model based on the Gogny energy density functional. The $(\beta,\gamma)$-deformation energy surface of…

Nuclear Theory · Physics 2019-03-13 K. Nomura , R. Rodríguez-Guzmán , L. M. Robledo

We derive the field-dependent masses in Fermi gauges for arbitrary scalar extensions of the Standard Model. These masses can be used to construct the effective potential for various models of new physics. We release a flexible…

High Energy Physics - Phenomenology · Physics 2022-12-09 Jonathan Zuk , Csaba Balazs , Andreas Papaefstathiou , Graham White

Reference system approach of non-relativistic electron fluid theory was adapted for calculation of characteristics of the electron-nuclear model at the densities typical of degenerate dwarfs. Two- and three correlation functions of…

Statistical Mechanics · Physics 2017-12-15 M. V. Vavrukh , D. V. Dzikovskyi , N. L. Tyshko

In the present work, we employ exact diagonalization for model systems on a real-space lattice to explicitly construct the exact density-to-potential and for the first time the exact density-to-wavefunction map that underly the…

Chemical Physics · Physics 2016-08-24 Tanja Dimitrov , Heiko Appel , Johanna I. Fuks , Angel Rubio

Density functional theory has become the workhorse of quantum physics, chemistry, and materials science. Within these fields, a broad range of applications needs to be covered. These applications range from solids to molecular systems, from…

Chemical Physics · Physics 2025-01-20 Christof Holzer , Yannick J. Franzke