Data-driven many-body potentials from density functional theory for aqueous phase chemistry

Chemical Physics Reviews, Journal Year: 2023, Volume and Issue: 4(1)

Published: Jan. 10, 2023

Density functional theory (DFT) has been applied to modeling molecular interactions in water for over three decades. The ubiquity of chemical and biological processes demands a unified understanding its physics, from the single molecule thermodynamic limit everything between. Recent advances development data-driven machine-learning potentials have accelerated simulation aqueous systems with DFT accuracy. However, anomalous properties condensed phase, where rigorous treatment both local non-local many-body (MB) is order, are often unsatisfactory or partially missing models water. In this review, we discuss based on provide comprehensive description general theoretical/computational framework reference data. This framework, coined MB-DFT, readily enables efficient dynamics (MD) simulations small molecules, gas phases, while preserving accuracy underlying model. Theoretical considerations emphasized, including role that delocalization error plays MB-DFT possibility elevate near-chemical-accuracy through density-corrected formalism. described detail, along application MB-MD recent extension reactive solution within quantum mechanics/MB mechanics (QM/MB-MM) scheme, using as prototypical solvent. Finally, identify open challenges future directions QM/MB-MM phases.

Language: Английский

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Reducing Exact Two-Component Theory for NMR Couplings to a One-Component Approach: Efficiency and Accuracy

Journal of Chemical Theory and Computation, Journal Year: 2023, Volume and Issue: 19(7), P. 2010 - 2028

Published: March 20, 2023

The self-consistent and complex spin-orbit exact two-component (X2C) formalism for NMR spin-spin coupling constants [ J. Chem. Theory Comput. 17, 2021, 3874-3994] is reduced to a scalar one-component ansatz. This way, the first-order response term can be partitioned into Fermi-contact (FC) spin-dipole (SD) interactions as well paramagnetic (PSO) contribution. FC+SD terms are real symmetric, while PSO purely imaginary antisymmetric. relativistic approach combined with modern density functional treatment up local hybrid functionals including of current density. Computational demands by factors 8-24 shown large tin compound consisting 137 atoms. Limitations ansatz critically assessed Sn, Pb, Pd, Pt compounds, i.e. not sufficient compounds featuring few heavy halogen

Language: Английский

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Benefits of Range-Separated Hybrid and Double-Hybrid Functionals for a Large and Diverse Data Set of Reaction Energies and Barrier Heights

The Journal of Physical Chemistry A, Journal Year: 2022, Volume and Issue: 126(32), P. 5492 - 5505

Published: Aug. 5, 2022

To better understand the thermochemical kinetics and mechanism of a specific chemical reaction, an accurate estimation barrier heights (forward reverse) reaction energies is vital. Because large size reactants transition state structures involved in real-life mechanistic studies (e.g., enzymatically catalyzed reactions), density functional theory remains workhorse for such calculations. In this paper, we have assessed performance 91 functionals modeling on chemically diverse data set (BH9) composed 449 organic chemistry reactions. We shown that range-separated hybrid perform than global hybrids BH9 energies. Except PBE-based nonempirical double hybrids, range separation exchange term helps improve The 16-parameter Berkeley hybrid, ωB97M(2), performs remarkably well both properties. However, our minimally empirical offer marginally accuracy ωB97M(2)

Language: Английский

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Computation of CCSD(T)-Quality NMR Chemical Shifts via Δ-Machine Learning from DFT

Journal of Chemical Theory and Computation, Journal Year: 2023, Volume and Issue: 19(12), P. 3601 - 3615

Published: June 1, 2023

NMR spectroscopy undoubtedly plays a central role in determining molecular structures across different chemical disciplines, and the accurate computational prediction of parameters is highly desirable. In this work, new Δ-machine learning approach presented to correct DFT-computed shifts using input features from calculation addition reference data at CCSD(T)/pcSseg-2 level theory with basis set extrapolation scheme. The model trained on containing 1000 optimized geometrically distorted small organic molecules comprising most elements first three periods for 7090 1H 4230 13C shifts. Applied PBE0/pcSseg-2 method, mean absolute deviation (MAD) internal shift test reduced by 81% 92% virtually no additional cost. For 12 DFT functional combinations, MAD ML-corrected ranges 0.021 0.039 ppm (1H) 0.38 1.07 (13C). Importantly, method consistently outperforms simple widely used linear regression correction technique. This behavior reproduced external benchmark sets, confirming generality robustness scheme, which can easily be applied DFT-based spectral simulations.

Language: Английский

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Toward Benchmark-Quality Ab Initio Predictions for 3d Transition Metal Electrocatalysts: A Comparison of CCSD(T) and ph-AFQMC

Journal of Chemical Theory and Computation, Journal Year: 2023, Volume and Issue: 19(18), P. 6208 - 6225

Published: Sept. 1, 2023

Generating accurate ab initio ionization energies for transition metal complexes is an important step toward the computational description of their electrocatalytic reactions. Benchmark-quality data required testing existing theoretical methods and developing new ones but complicated to obtain many compounds due potential presence both strong dynamical static electron correlation. In this regime, it questionable whether so-called gold standard, coupled cluster with singles, doubles, perturbative triples (CCSD(T)), provides desired level accuracy─roughly 1-3 kcal/mol. work, we compiled a test set 28 3d metal-containing molecules relevant homogeneous electrocatalysis (termed 3dTMV) computed vertical (ionization potentials) CCSD(T) phaseless auxiliary-field quantum Monte Carlo (ph-AFQMC) in def2-SVP basis set. A substantial effort has been made converge away bias ph-AFQMC reference values. We assess wide variety multireference diagnostics find that spin-symmetry breaking CCSD wave function PBE0 density functional correlate well our analysis multiconfigurational functions. propose quantitative criteria based on symmetry delineate correlation regimes inside which appropriately performed can produce mean absolute deviations from values roughly 2 kcal/mol or less outside expected fail. also present preliminary assessment theory (DFT) functionals 3dTMV

Language: Английский

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Optimization of the r²SCAN-3c Composite Electronic-Structure Method for Use with Slater-Type Orbital Basis Sets

The Journal of Physical Chemistry A, Journal Year: 2022, Volume and Issue: 126(23), P. 3826 - 3838

Published: June 2, 2022

The "Swiss army knife" composite density functional electronic-structure method r2SCAN-3c (J. Chem. Phys.2021, 154, 064103) is extended and optimized for the use with Slater-type orbital basis sets. meta generalized-gradient approximation (meta-GGA) r2SCAN by Furness et al. combined a tailor-made polarized triple-ζ atomic (STO) set (mTZ2P), semiclassical London dispersion correction (D4), geometrical counterpoise (gCP) correction. Relativistic effects are treated explicitly scalar-relativistic zeroth-order regular (SR-ZORA). performance of new implementation assessed on eight geometry 74 energy benchmark sets, including extensive GMTKN55 database as well recent sets such ROST61 IONPI19. In optimizations, STO-based either par or more accurate than hybrid M06-2X-D3(0)/TZP. calculations, overall accuracy similar to original Gaussian-type orbitals (GTO), but basic properties, intermolecular noncovalent interactions, barrier heights better described STO approach, resulting in lower weighted mean absolute deviation (WTMAD-2(STO) = 7.15 vs 7.50 kcal mol-1 method) database. STO-optimized outperforms many conventional hybrid/QZ approaches most common applications at fraction their cost. reliable, robust, STOs promising alternative GTOs can be generally used broad field quantum chemical problems.

Language: Английский

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Conformational energies of biomolecules in solution: Extending the MPCONF196 benchmark with explicit water molecules

Journal of Computational Chemistry, Journal Year: 2023, Volume and Issue: 45(7), P. 419 - 429

Published: Nov. 19, 2023

Abstract A prerequisite for the computational prediction of molecular properties like conformational energies biomolecules is a reliable, robust, and computationally affordable method usually selected according to its performance relevant benchmark sets. However, most these sets comprise molecules in gas phase do not cover interactions with solvent, even though typically occur aqueous solution. To address this issue, we introduce explicit water solvated version gas‐phase set containing 196 conformers 13 peptides other macrocycles, namely MPCONF196 [J. Řezáč et al., JCTC 2018 , 14 1254–1266], provide very accurate PNO‐LCCSD(T)‐F12b/AVQZ' reference values. The novel solvMPCONF196 features two additional challenges beyond description phase: conformer–water water–water interactions. overall best performing double hybrid revDSDPBEP86‐D4/def2‐QZVPP yielding almost coupled cluster quality. Furthermore, some (meta‐)GGAs functionals B97M‐V B97M‐D large basis reproduce an MAD below 1 kcal mol . If more efficient methods are required, composite DFT‐method rSCAN‐3c (MAD 1.2 mol) good alternative, when polypeptides or macrocycles than 500–1000 atoms focus, semi‐empirical GFN2‐xTB MMFF94 force field (for systems) recommended.

Language: Английский

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Dispersion-corrected r2SCAN based double-hybrid functionals

The Journal of Chemical Physics, Journal Year: 2023, Volume and Issue: 159(22)

Published: Dec. 8, 2023

The regularized and restored semi-local meta-generalized gradient approximation (meta-GGA) exchange-correlation functional r2SCAN [Furness et al., J. Phys. Chem. Lett. 11, 8208-8215 (2020)] is used to create adiabatic-connection-derived global double-hybrid functionals employing spin-opposite-scaled MP2. 0-DH, CIDH, QIDH, 0-2 type are assessed as a starting point for further modification. Variants with 50% 69% Hartree-Fock exchange (HFX) empirically optimized (Pr2SCAN50 Pr2SCAN69), the effect of MP2-regularization (κPr2SCAN50) range-separated HFX (ωPr2SCAN50) evaluated. All combined state-of-the-art London dispersion corrections D4 NL. resulting comprehensively their performance on main-group metal-organic thermochemistry 90 different benchmark sets containing 25 800 data points. These include extensive GMTKN55 database, additional chemistry, multiple transition-metal complexes, including ROST61, MOR41, MOBH35 sets. As main target this study development broadly applicable, robust low empiricism, special focus put variants moderate amounts (50%), which compared so far successful PWPB95-D4 (50% HFX, 20% MP2 correlation) functional. overall best variant, ωPr2SCAN50-D4, performs well thermochemistry, followed by Pr2SCAN69-D4 that offers slight edge Pr2SCAN50-D4 robustly across all tested four functionals, Pr2SCAN69-D4, Pr2SCAN50-D4, κPr2SCAN50-D4, outperform

Language: Английский

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Symmetry and reactivity of π-systems in electric and magnetic fields: a perspective from conceptual DFT

Physical Chemistry Chemical Physics, Journal Year: 2024, Volume and Issue: 26(21), P. 15156 - 15180

Published: Jan. 1, 2024

Fukui function for nucleophilic attack on H 2 CO in a parallel magnetic field showing significantly reduced Bürgi–Dunitz angle.

Language: Английский

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The Role of Methyl Substitution in Spin Crossover of Fe(III) Complexes with Pentadentate Schiff Base Ligands

Inorganics, Journal Year: 2025, Volume and Issue: 13(2), P. 57 - 57

Published: Feb. 15, 2025

A series of mononuclear complexes, [Fe(L5)(bylim)](BPh4), where L5 represents a pentadentate Schiff base ligand, bylim is 1-benzyl-1-imidazole, and BPh4− the tetraphenylborate anion, was synthesized. The determined crystal structures indicate absence significant cooperative interactions, which influence properties eventual spin transition. Changes in magnetic behavior induced by substitution ligand were investigated through susceptibility measurements. It found that only complexes containing non-substituted secondary amino group exhibit some form crossover, whereas majority those with methyl substituent remain high-spin state across entire measured temperature range (2–300 K). changes amine further explored theoretical calculations at DFT CASSCF/NEVPT2 levels theory. topology energetics electron density atomic charges QT-AIM calculations.

Language: Английский

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