Beyond Electrons: Correlation and Self‐Energy in Multicomponent Density Functional Theory

ChemPhysChem, Journal Year: 2024, Volume and Issue: 25(13)

Published: March 8, 2024

Abstract Post‐Kohn‐Sham methods are used to evaluate the ground‐state correlation energy and orbital self‐energy of systems consisting multiple flavors different fermions. Starting from multicomponent density functional theory, suitable ways arrive at corresponding random‐phase approximation Green's function approximation, including relativistic effects, outlined. Given importance both this in development modern Kohn–Sham approximations, work will provide a foundation design advanced approximations. Additionally, quasiparticle energies needed study light‐matter interactions with Bethe‐Salpeter equation.

Language: Английский

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Robust relativistic many-body Green’s function based approaches for assessing core ionized and excited states

The Journal of Chemical Physics, Journal Year: 2023, Volume and Issue: 159(4)

Published: July 28, 2023

A two-component contour deformation (CD) based GW method that employs frequency sampling to drastically reduce the computational effort when assessing quasiparticle states far away from Fermi level is outlined. Compared canonical CD-GW method, scaling reduced by an order of magnitude without sacrificing accuracy. This allows for efficient calculation core ionization energies. The improved efficiency used provide benchmarks ionized states, comparing performance 15 density functional approximations as Kohn-Sham starting points calculations on a set 65 energies 32 small molecules. Contrary valence prefer functionals with only moderate amount Hartree-Fock exchange. Moreover, modern ab initio local hybrid are also shown excellent generalized references calculations. Furthermore, core-valence separated Bethe-Salpeter equation (CVS-BSE) CVS-BSE convenient tool probe excited states. latter tested 40 excitations eight inorganic Results excitation and corresponding absorption cross sections found be in agreement those reference damped response BSE

Language: Английский

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A Guide to Molecular Properties from the Bethe–Salpeter Equation

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

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Toward a correct treatment of core properties with local hybrid functionals

Journal of Computational Chemistry, Journal Year: 2023, Volume and Issue: 44(32), P. 2461 - 2477

Published: Aug. 28, 2023

In local hybrid functionals (LHs), a mixing function (LMF) determines the position-dependent exact-exchange admixture. We report new LHs that focus on an improvement of LMF in core region while retaining or partly improving upon high accuracy valence exhibited by LH20t functional. The suggested pt-LMFs are based Padé form and modify previously used ratio between von Weizsäcker Kohn-Sham kinetic energies different powers density to enable flexibly improved approximations correct high-density iso-orbital limits relevant for innermost region. Using TDDFT calculations set K-shell excitations second- third-period systems including accurate state-of-the-art relativistic orbital corrections, part is optimized, optimized as reported test sets atomization reaction barriers (Haasler et al., J Chem Theory Comput 2020, 16, 5645). completed calibration minimizes spurious nondynamical correlation effects caused gauge ambiguities exchange-energy densities, well B95c meta-GGA correlation. resulting LH23pt functional relates previous but specifically improves

Language: Английский

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Zero-field splitting parameters within exact two-component theory and modern density functional theory using seminumerical integration

The Journal of Chemical Physics, Journal Year: 2023, Volume and Issue: 159(19)

Published: Nov. 21, 2023

An efficient implementation of zero-field splitting parameters based on the work Schmitt et al. [J. Chem. Phys. 134, 194113 (2011)] is presented. Seminumerical integration techniques are used for two-electron spin-dipole contribution and response equations spin-orbit perturbation. The original formulation further generalized. First, it extended to meta-generalized gradient approximations local hybrid functionals. For these functional classes, paramagnetic current density considered in coupled-perturbed Kohn-Sham perturbation term. Second, formulated within relativistic exact two-component theory screened nuclear (SNSO) approximation. accuracy demonstrated transition-metal diatomic main-group compounds. efficiency assessed Mn Mo complexes. Here, found that coarse grids seminumerical schemes lead drastic speedups while introducing clearly negligible errors. In addition, SNSO approximation substantially reduces computational demands leads very similar results as mean field Ansatz.

Language: Английский

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A General and Transferable Local Hybrid Functional for Electronic Structure Theory and Many-Fermion Approaches

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

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Fully Tin‐Coated Coinage Metal Ions: A Pincer‐Type Bis‐stannylene Ligand for Exclusive Tetrahedral Complexation

Chemistry - A European Journal, Journal Year: 2022, Volume and Issue: 29(27)

Published: Dec. 19, 2022

The synthesis of a novel bis-stannylene pincer ligand and its complexation with coinage metals (CuI , AgI AuI ) are described. All metal centres in tetrahedral coordination environments the solid state exclusively coordinated by four neutral SnII donors. 119 Sn NMR provided information about behaviour solution. isolated compounds have photoluminescent properties, these were investigated at low elevated temperatures. Compared to free ligand, led an increase luminescence intensity. new detail through all-electron relativistic density functional theory (DFT) calculations.

Language: Английский

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Efficient treatment of relativistic effects with periodic density functional methods: Energies, gradients, and stress tensors

Physical review. B./Physical review. B, Journal Year: 2024, Volume and Issue: 109(16)

Published: April 23, 2024

The implementation of an efficient self-consistent field (SCF) method including both scalar-relativistic effects and spin-orbit interaction in density functional theory (DFT) is presented. We make use Gaussian-type orbitals all integrals are evaluated real space. Our supports approximations up to the level meta-generalized gradient for SCF energies gradients. latter can be used compute stress tensor consequently allow us optimize cell structure. Considering requires extension standard procedures a two-component formalism noncollinear approach open-shell systems. Here, we implemented canonical Scalmani-Frisch DFT formalisms, with hybrid range-separated functionals being presently restricted energies. demonstrate efficiency relevance electronic structure discrete systems periodic one three dimensions.

Language: Английский

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BSE@GW Prediction of Charge Transfer Exciton in Molecular Complexes: Assessment of Self-Energy and Exchange-Correlation Dependence

The Journal of Physical Chemistry A, Journal Year: 2024, Volume and Issue: unknown

Published: July 16, 2024

The Bethe–Salpeter equation using the GW approximation to self-energy (BSE@GW) is a computationally attractive method for studying electronic excitation from first principles within many-body Green's function theory framework. We examine its dependence on underlying exchange-correlation (XC) as well predicting charge transfer exciton formation at representative type-II interfaces between molecular systems of tetrachloro-1,2-benzoquinone (TCBQ) and acene derivatives. For XC approximation, we consider several widely used generalized gradient (GGA) hybrid GGA functionals. recently proposed renormalized singles approach by Yang coauthors [J. Phys. Chem. Lett. 2019, 10 (3), 447–452; J. Theory Comput. 2022, 18, 7570–7585] in addition other commonly employed approximated schemes. demonstrate reliable prediction BSE@GW level theory.

Language: Английский

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Establishing Family Relations in Group 15 Halogenido Metalates with the Largest Molecular Antimony Iodide Anion

Chemistry - A European Journal, Journal Year: 2022, Volume and Issue: 29(2)

Published: Oct. 4, 2022

Studying structurally related families of compounds is a valuable tool in understanding and predicting material properties has been extensively used for metal halide perovskites. Due to the variable anion structures group 15 halogenido metalates, similar family relations are still largely missing. Herein, we present featuring [Sb2n I6n+4 ]4- anions, including first n=5 member [Hpyz]4 [Sb10 I34 ] (Hpyz=pyrazinium), which contains largest pentelate reported date. The optical n=1-5 anions show clear trend as well an outlier, low band gap 1.72 eV ], that can be understood using quantum chemical investigations. Also SbI3 [H2 NMe2 ]3 [SbI6 compound single octahedral ]3- unit, limiting cases, structure-property relationships established metalates way perovskites, thus providing framework new known this emerging class materials.

Language: Английский

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