Application of the Adiabatic Connection Random Phase Approximation to Electron-Nucleus Hyperfine Coupling Constants DOI Creative Commons
Florian Bruder, Florian Weigend, Yannick J. Franzke

et al.

Published: June 6, 2024

The electron-nucleus hyperfine coupling constant is a challenging property for density functional methods. For accurate results, hybrid functionals with large amount of exact exchange are often needed and there no clear "one-for-all" functional, which describes the interaction set nuclei. To alleviate this unfavorable situation, we apply adiabatic connection random phase approximation (RPA) in its post-Kohn-Sham fashion to as first test. simplicity, only Fermi-contact spin--dipole terms calculated within non-relativistic scalar-relativistic two-component framework. This requires solve single coupled-perturbed Kohn-Sham equation evaluate relaxed matrix, comes modest increase computational demands. RPA performs remarkably well substantially improves upon (KS) starting point while also reducing dependence on KS reference. main-group systems, outperforms global, range-separated, local functionals—at similar costs. transition-metal compounds lanthanide complexes, performance observed. In contrast, related post-Hartree-Fock methods such Mølller-Plesset perturbation theory or CC2 perform worse than semilocal functionals.

Language: Английский

Restoring rotational symmetry of multicomponent wavefunctions with nuclear orbitals DOI Creative Commons
Félix Moncada, Andrés Reyes, Lars G. M. Pettersson

et al.

The Journal of Chemical Physics, Journal Year: 2025, Volume and Issue: 162(2)

Published: Jan. 8, 2025

In this work, we present a non-orthogonal configuration interaction (NOCI) approach to address the rotational corrections in multicomponent quantum chemistry calculations where hydrogen nuclei and electrons are described with orbitals under Hartree–Fock (HF) density functional theory (DFT) frameworks. The required systems such as diatomic (HX) nonlinear triatomic molecules (HXY), localized broken-symmetry nuclear have lower energy than delocalized correct symmetry. By restoring symmetry proposed NOCI approach, demonstrate significant improvements proton binding predictions at HF level, average of 0.46 eV for HX 0.23 HXY molecules. For computing excitation energies, our results indicate that kinetic consistently accurate, while discrepancies arise total predictions, primarily from an incomplete treatment dynamical correlation effects. Rotational DFT calculations, using epc17-2 proton–electron functional, lead overestimation energies. This is result double-counting effects off-diagonal terms. As correction, propose scaling scheme effectively adjusts contributions, bringing into close agreement reference CCSD(T) data. scaled corrections, on average, increase by 0.055 0.025 yield deviations 1.0 cm−1 transitions.

Language: Английский

Citations

0
A Guide to Molecular Properties from the Bethe–Salpeter Equation DOI
Christof Holzer, Yannick J. Franzke

The Journal of Physical Chemistry Letters, Journal Year: 2025, Volume and Issue: unknown, P. 3980 - 3990

Published: April 14, 2025

The Bethe-Salpeter equation (BSE) combined with the Green's function GW method has been successfully transformed into a robust computational tool to describe light-matter interactions and excitation spectra for molecules, solids, materials from first principles. Due its ability accurately charge transfer Rydberg excitations, GW-BSE is already an established cost-efficient alternative time-dependent density functional theory. This raises question whether approach can become more general framework molecular properties beyond energies. In this Mini-Review, we recapitulate recent endeavors along point in terms of both theoretical practical developments quantum chemistry, physical related fields. doing so, provide guidelines current applications chemical challenges collaboration experimentalists as well future extended toolkit.

Language: Английский

Citations

0
A General and Transferable Local Hybrid Functional for Electronic Structure Theory and Many-Fermion Approaches DOI
Christof Holzer, Yannick J. Franzke

Journal of Chemical Theory and Computation, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 20, 2024

Density functional theory has become the workhorse of quantum physics, chemistry, and materials science. Within these fields, a broad range applications needs to be covered. These from solids molecular systems, organic inorganic or even electrons other Fermions, such as protons muons. This is emphasized by plethora density approximations that have been developed for various cases. In this work, two new local hybrid exchange-correlation functionals are constructed first-principles, promoting generality transferability. We show constraint satisfaction can achieved admixtures with full exact exchange, without sacrificing accuracy. The performance CHYF-PBE CHYF-B95 assessed thermochemical properties, excitation energies, Mössbauer isomer shifts, NMR spin-spin coupling constants, shieldings magnetizabilities, EPR hyperfine constants. Here, shows excellent throughout all tests numerically robust only requiring small grids converged results. Additionally, both easily generalized arbitrary Fermions shown electron-proton correlation energies. Therefore, we outline generated in way general purpose tools mechanical studies.

Language: Английский

Citations

3
Local Electronic Correlation in Multicomponent Møller–Plesset Perturbation Theory DOI Creative Commons
Lukas Hasecke, Ricardo A. Mata

Journal of Chemical Theory and Computation, Journal Year: 2024, Volume and Issue: 20(22), P. 9928 - 9938

Published: Nov. 8, 2024

We present in this contribution the first application of local correlation context multicomponent methods. Multicomponent approaches allow for targeted simulation electrons together with other Fermions (most commonly protons) as quantum particles. These methods have become increasingly popular over last years, particularly description nuclear effects (in strong hydrogen bonds, proton tunneling, and many more). However, most implementations are still based on canonical formulations wave function theory, which we know decades to be computationally inefficient capturing dynamical effects. Local approaches, use pair natural orbitals (PNOs), enable asymptotically linear scaling computational costs very little impact overall accuracy. In context, efficient density fitting approximations integral calculation proves essential. start by discussing our implementation density-fitted NEO-MP2 NEO-PNO-LMP2, upgrading electronic treatment up PNO coupled cluster level theory. Several challenging examples provided benchmark method terms accuracy well cost scaling. Following appropriate protocols, anharmonic corrections localized X-H stretches can applied routinely overhead.

Language: Английский

Citations

2
Application of the Adiabatic Connection Random Phase Approximation to Electron–Nucleus Hyperfine Coupling Constants DOI Creative Commons
Florian Bruder, Florian Weigend, Yannick J. Franzke

et al.

The Journal of Physical Chemistry A, Journal Year: 2024, Volume and Issue: 128(34), P. 7298 - 7310

Published: Aug. 20, 2024

The electron–nucleus hyperfine coupling constant is a challenging property for density functional methods. For accurate results, hybrid functionals with large amount of exact exchange are often needed and there no clear "one-for-all" which describes the interaction set nuclei. To alleviate this unfavorable situation, we apply adiabatic connection random phase approximation (RPA) in its post-Kohn–Sham fashion to as first test. simplicity, only Fermi-contact spin–dipole terms calculated within nonrelativistic scalar-relativistic two-component framework. This requires solve single coupled-perturbed Kohn–Sham equation evaluate relaxed matrix, comes modest increase computational demands. RPA performs remarkably well substantially improves upon (KS) starting point while also reducing dependence on KS reference. main-group systems, outperforms global, range-separated, local functionals─at similar costs. transition-metal compounds lanthanide complexes, performance observed. In contrast, related post-Hartree–Fock methods such Møller–Plesset perturbation theory or CC2 perform worse than semilocal functionals.

Language: Английский

Citations

1
Application of the Adiabatic Connection Random Phase Approximation to Electron-Nucleus Hyperfine Coupling Constants DOI Creative Commons
Florian Bruder, Florian Weigend, Yannick J. Franzke

et al.

Published: June 6, 2024

The electron-nucleus hyperfine coupling constant is a challenging property for density functional methods. For accurate results, hybrid functionals with large amount of exact exchange are often needed and there no clear "one-for-all" functional, which describes the interaction set nuclei. To alleviate this unfavorable situation, we apply adiabatic connection random phase approximation (RPA) in its post-Kohn-Sham fashion to as first test. simplicity, only Fermi-contact spin--dipole terms calculated within non-relativistic scalar-relativistic two-component framework. This requires solve single coupled-perturbed Kohn-Sham equation evaluate relaxed matrix, comes modest increase computational demands. RPA performs remarkably well substantially improves upon (KS) starting point while also reducing dependence on KS reference. main-group systems, outperforms global, range-separated, local functionals—at similar costs. transition-metal compounds lanthanide complexes, performance observed. In contrast, related post-Hartree-Fock methods such Mølller-Plesset perturbation theory or CC2 perform worse than semilocal functionals.

Language: Английский

Citations

0
Application of the Adiabatic Connection Random Phase Approximation to Electron-Nucleus Hyperfine Coupling Constants DOI Creative Commons
Florian Bruder, Florian Weigend, Yannick J. Franzke

et al.

Published: June 6, 2024

The electron-nucleus hyperfine coupling constant is a challenging property for density functional methods. For accurate results, hybrid functionals with large amount of exact exchange are often needed and there no clear "one-for-all" functional, which describes the interaction set nuclei. To alleviate this unfavorable situation, we apply adiabatic connection random phase approximation (RPA) in its post-Kohn-Sham fashion to as first test. simplicity, only Fermi-contact spin--dipole terms calculated within non-relativistic scalar-relativistic two-component framework. This requires solve single coupled-perturbed Kohn-Sham equation evaluate relaxed matrix, comes modest increase computational demands. RPA performs remarkably well substantially improves upon (KS) starting point while also reducing dependence on KS reference. main-group systems, outperforms global, range-separated, local functionals—at similar costs. transition-metal compounds lanthanide complexes, performance observed. In contrast, related post-Hartree-Fock methods such Mølller-Plesset perturbation theory or CC2 perform worse than semilocal functionals.

Language: Английский

Citations

0