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We consider conformal field theories around points of large twist degeneracy. Examples of this are theories with weakly broken higher spin symmetry and perturbations around generalised free fields. At the degenerate point we introduce twist…

High Energy Physics - Theory · Physics 2017-09-20 Luis F. Alday

Time-dependent density-functional theory (TDDFT) is deemed to be a formally rigorous way of dealing with the time-evolution of a many-electron system at the level of electron densities rather than the underlying wavefunctions, which in turn…

Chemical Physics · Physics 2024-11-26 Jochen Schirmer

When an electron is confined to a triangular atomic thick layer of graphene [1-5] with zig-zag edges, its energy spectrum collapses to a shell of degenerate states at the Fermi level (Dirac point) [6-9]. The degeneracy is proportional to…

Materials Science · Physics 2013-05-29 A. D. Guclu , P. Potasz , O. Voznyy , M. Korkusinski , P. Hawrylak

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…

We present a numerical modeling workflow based on machine learning (ML) which reproduces the the total energies produced by Kohn-Sham density functional theory (DFT) at finite electronic temperature to within chemical accuracy at negligible…

It is shown here that Kohn-Sham equations cannot be derived from Hohenberg-Kohn theory without an additional postulate. Assuming that a functional derivative with respect to total electron density exists leads in general to a theory…

Condensed Matter · Physics 2007-05-23 R. K. Nesbet

The kinetic energy (KE) kernel, which is defined as the second order functional derivative of the KE functional with respect to density, is the key ingredient to the construction of KE models for orbital free density functional theory…

Materials Science · Physics 2025-05-15 Zhandos A. Moldabekov , Xuecheng Shao , Michele Pavanello , Jan Vorberger , Tobias Dornheim

The self consistent version of the density functional theory is presented, which allows to calculate the ground state and dynamic properties of finite multi-electron systems. An exact functional equation for the effective interaction, from…

Materials Science · Physics 2017-08-23 M. Ya. Amusia , A. Z. Msezane , V. R. Shaginyan

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 show that using complex, spin-restricted orbitals (cR) in Kohn-Sham density functional theory (KS-DFT) allows one to access a new class of densities that is not accessible by either spin-restricted (RKS) or spin-unrestricted (UKS)…

Chemical Physics · Physics 2019-09-13 Joonho Lee , Luke W. Bertels , Martin Head-Gordon

Quantum mechanical methods based on the density functional theory (DFT) offer a realistic possibility of first-principles design of organic donor-acceptor systems and engineered band-gap materials. This promise is contingent upon the…

Chemical Physics · Physics 2013-12-03 Marcin Modrzejewski , Grzegorz Chałasiński , Małgorzata M. Szczęśniak

Calculations in Kohn-Sham density functional theory crucially rely on high-quality approximations for the exchange-correlation (xc) functional. Standard local and semi-local approximations fail to predict the ionization potential (IP) and…

Materials Science · Physics 2023-05-03 Sharon Lavie , Yuli Goshen , Eli Kraisler

The inverse problem of Kohn-Sham density functional theory (DFT) is often solved in an effort to benchmark and design approximate exchange-correlation potentials. The forward and inverse problems of DFT rely on the same equations but the…

Chemical Physics · Physics 2017-08-02 Daniel Jensen , Adam Wasserman

Fromager and Lasorne [Electron. Struct. 6 025002 (2024)] have recently derived an in-principle exact Kohn-Sham density functional theory (KS-DFT) of electrons and nuclei, where the nuclear density and the (so-called conditional) electronic…

Chemical Physics · Physics 2026-03-10 Lucien Dupuy , Benjamin Lasorne , Emmanuel Fromager

When running time-dependent density functional theory (TDDFT) calculations for real-time simulations of non-equilibrium dynamics, the user has a choice of initial Kohn-Sham state, and typically a Slater determinant is used. We explore the…

Chemical Physics · Physics 2016-08-24 Johanna I. Fuks , Soeren E. B. Nielsen , Michael Ruggenthaler , Neepa T. Maitra

The Hohenberg-Kohn theorem of density-functional theory (DFT) is broadly considered the conceptual basis for a full characterization of an electronic system in its ground state by just the one-body particle density. Part I of this review…

The density-functional based symmetry-adapted perturbation theory [SAPT(DFT)] has been applied to the argon, krypton, and benzene dimers. It is shown that--at a small fraction of computational costs--SAPT(DFT) can provide similar accuracies…

Chemical Physics · Physics 2007-05-23 Rafał Podeszwa , Krzysztof Szalewicz

We present the extension of Frozen Density Embedding (FDE) theory to real-time Time Dependent Density Functional Theory (rt-TDDFT). FDE a is DFT-in-DFT embedding method that allows to partition a larger Kohn-Sham system into a set of…

Chemical Physics · Physics 2015-06-23 Alisa Krishtal , Davide Ceresoli , Michele Pavanello

Kohn-Sham density functional theory is one of the most widely used electronic structure theories. In the pseudopotential framework, uniform discretization of the Kohn-Sham Hamiltonian generally results in a large number of basis functions…

Numerical Analysis · Mathematics 2015-05-27 Lin Lin , Jianfeng Lu , Lexing Ying , E. Weinan

We introduce a practical hybrid approach that combines orbital-free density functional theory (DFT) with Kohn-Sham DFT for speeding up first-principles molecular dynamics simulations. Equilibrated ionic configurations are generated using…