Density functionals based on the mathematical structure of the strong‐interaction limit of DFT

Wiley Interdisciplinary Reviews Computational Molecular Science, Journal Year: 2022, Volume and Issue: 13(2)

Published: Aug. 29, 2022

Abstract While in principle exact, Kohn–Sham density functional theory—the workhorse of computational chemistry—must rely on approximations for the exchange–correlation functional. Despite staggering successes, present‐day still struggle when effects electron–electron correlation play a prominent role. The limit which electronic Coulomb repulsion completely dominates offers well‐defined mathematical framework that provides insight new able to deal with strong correlation. In particular, structure this limit, is now well‐established thanks its reformulation as an optimal transport problem, points use very different ingredients (or features) respect traditional ones used present approximations. We focus strategies these build chemistry and highlight future promising directions. This article categorized under: Electronic Structure Theory > Density Functional

Language: Английский

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Radicals in aqueous solution: assessment of density-corrected SCAN functional

Physical Chemistry Chemical Physics, Journal Year: 2023, Volume and Issue: 25(31), P. 20817 - 20836

Published: Jan. 1, 2023

We study self-interaction effects in solvated and strongly-correlated cationic molecular clusters, with a focus on the hydroxyl radical. To address issue, we apply DC-r2SCAN method, auxiliary density matrix approach. Validating our method through simulations of bulk liquid water, demonstrate that maintains structural accuracy r2SCAN while effectively addressing spin localization issues. Extending analysis to find hemibonded motif [CH3S∴CH3SH]+ cluster is disrupted simulation, contrast preserves (three-electron-two-center)-bonded motif. Similarly, for [SH∴SH2]+ cluster, restores leakage, predicts weaker hemibond formation influenced by solvent-solute interactions. Our findings potential combined improve electronic structure calculations, providing insights into properties clusters. This work contributes advancement corrected theory offers computational framework modeling condensed phase systems intricate correlation effects.

Language: Английский

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Electronic-Structure Properties from Atom-Centered Predictions of the Electron Density

Journal of Chemical Theory and Computation, Journal Year: 2022, Volume and Issue: 19(14), P. 4451 - 4460

Published: Dec. 1, 2022

The electron density of a molecule or material has recently received major attention as target quantity machine-learning models. A natural choice to construct model that yields transferable and linear-scaling predictions is represent the scalar field using multicentered atomic basis analogous routinely used in fitting approximations. However, nonorthogonality poses challenges for learning exercise, it requires accounting all components at once. We devise gradient-based approach directly minimize loss function regression problem an optimized highly sparse feature space. In so doing, we overcome limitations associated with adopting atom-centered learn over arbitrarily complex data sets, obtaining very accurate comparatively small training set. enhanced framework tested on 32-molecule periodic cells liquid water, presenting enough complexity require optimal balance between accuracy computational efficiency. show starting from predicted single Kohn-Sham diagonalization step can be performed access total energy carry error just 0.1 meV/atom respect reference functional calculations. Finally, test our method heterogeneous QM9 benchmark set, showing fraction derive ground-state energies within chemical accuracy.

Language: Английский

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Hydration Structure of Na⁺ and K⁺ Ions in Solution Predicted by Data-Driven Many-Body Potentials

The Journal of Physical Chemistry B, Journal Year: 2022, Volume and Issue: 126(45), P. 9349 - 9360

Published: Nov. 3, 2022

The hydration structure of Na+ and K+ ions in solution is systematically investigated using a hierarchy molecular models that progressively include more accurate representations many-body interactions. We found conventional empirical pairwise additive force field commonly used biomolecular simulations unable to reproduce the extended X-ray absorption fine (EXAFS) spectra for both ions. In contrast, progressive inclusion effects rigorously derived from expansion energy allows MB-nrg potential functions (PEFs) achieve nearly quantitative agreement with experimental EXAFS spectra, thus enabling development molecular-level picture solution. Since PEFs have already been shown accurately describe isomeric equilibria vibrational small ion–water clusters gas phase, present study demonstrates effectively represent long-sought-after able correctly predict properties ionic aqueous systems liquid which has so far remained elusive.

Language: Английский

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Toward routine Kohn–Sham inversion using the “Lieb-response” approach

The Journal of Chemical Physics, Journal Year: 2023, Volume and Issue: 158(6)

Published: Feb. 8, 2023

Kohn-Sham (KS) inversion, in which the effective KS mean-field potential is found for a given density, provides insights into nature of exact density functional theory (DFT) that can be exploited development approximations. Unfortunately, despite significant and sustained progress both software libraries, inversion remains rather difficult practice, especially finite basis sets. The present work presents method, dubbed "Lieb-response" approach, naturally works with existing Fock-matrix DFT infrastructure sets, numerically efficient, directly meaningful matrix energy quantities pure-state ensemble systems. Some additional yields potential. It thus enables routine even systems, as illustrated variety problems within this work, outputs used embedding schemes or machine learning effect sets on also analyzed investigated.

Language: Английский

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