In Silico Chemical Experiments in the Age of AI: From Quantum Chemistry to Machine Learning and Back

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(30)

Published: May 25, 2024

Abstract Computational chemistry is an indispensable tool for understanding molecules and predicting chemical properties. However, traditional computational methods face significant challenges due to the difficulty of solving Schrödinger equations increasing cost with size molecular system. In response, there has been a surge interest in leveraging artificial intelligence (AI) machine learning (ML) techniques silico experiments. Integrating AI ML into increases scalability speed exploration space. remain, particularly regarding reproducibility transferability models. This review highlights evolution from, complementing, or replacing energy property predictions. Starting from models trained entirely on numerical data, journey set forth toward ideal model incorporating physical laws quantum mechanics. paper also reviews existing their intertwining, outlines roadmap future research, identifies areas improvement innovation. Ultimately, goal develop architectures capable accurate transferable solutions equation, thereby revolutionizing experiments within materials science.

Language: Английский

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Some Recent Advances in Density-Based Reactivity Theory

The Journal of Physical Chemistry A, Journal Year: 2024, Volume and Issue: 128(7), P. 1183 - 1196

Published: Feb. 8, 2024

Establishing a chemical reactivity theory in density functional (DFT) language has been our intense research interest the past two decades, exemplified by determination of steric effect and stereoselectivity, evaluation electrophilicity nucleophilicity, identification strong weak interactions, formulation cooperativity, frustration, principle chirality hierarchy. In this Featured Article, we first overview four density-based frameworks DFT to appreciate understanding, including conceptual DFT, use associated quantities, information-theoretic approach, orbital-free then present few recent advances these as well new applications from studies. To that end, will introduce relationship among frameworks, determining entire spectrum interactions with Pauli energy derivatives, performing topological analyses extending excited states. Applications examine physiochemical properties external electric fields evaluate polarizability for proteins crystals are discussed. A possible directions future development followed, special emphasis on its merger machine learning.

Language: Английский

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Accurate Structures and Rotational Constants of Steroid Hormones at DFT Cost: Androsterone, Testosterone, Estrone, β-Estradiol, and Estriol

The Journal of Physical Chemistry A, Journal Year: 2024, Volume and Issue: 128(13), P. 2629 - 2642

Published: March 26, 2024

A comprehensive analysis of the structural, conformational, and spectroscopic properties in gas phase has been performed for five prototypical steroid hormones, namely, androsterone, testosterone, estrone, β-estradiol, estriol. The revDSD-PBEP86 double-hybrid functional conjunction with D3BJ empirical dispersion a suitable triple-ζ basis set provides accurate conformational energies equilibrium molecular structures, latter being further improved by proper account core–valence correlation. Average deviations within 0.1% between computed experimental ground state rotational constants are reached when adding to those values vibrational corrections obtained at cost standard harmonic frequencies thanks use new computational tool. Together intrinsic interest studied accuracy results DFT molecules containing about 50 atoms paves way toward investigations other flexible bricks life.

Language: Английский

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Unbiased Comparison between Theoretical and Experimental Molecular Structures and Properties: Toward an Accurate Reduced-Cost Evaluation of Vibrational Contributions

Journal of Chemical Theory and Computation, Journal Year: 2024, Volume and Issue: 20(7), P. 2842 - 2857

Published: April 1, 2024

The tremendous development of hardware and software is constantly increasing the role quantum chemical (QC) computations in assignment interpretation experimental results. However, an unbiased comparison between theory experiment requires proper account vibrational averaging effects. In particular, high-resolution spectra gas phase are now available for molecules containing up to about 50 atoms, which too large a brute-force approach with QC methods sufficient accuracy. present paper, we introduce hybrid approaches, allow accurate evaluation effects this size beyond harmonic approximation, special attention being devoted rotational constants. After validation new tools relatively small molecules, β-estradiol hormone prototypical molecular motor have been considered witness feasibility molecules.

Language: Английский

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Overcoming the barrier of orbital-free density functional theory for molecular systems using deep learning

Nature Computational Science, Journal Year: 2024, Volume and Issue: 4(3), P. 210 - 223

Published: March 11, 2024

Language: Английский

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Toward the Next Generation of Density Functionals: Escaping the Zero-Sum Game by Using the Exact-Exchange Energy Density

Accounts of Chemical Research, Journal Year: 2024, Volume and Issue: 57(13), P. 1815 - 1826

Published: June 21, 2024

ConspectusKohn–Sham density functional theory (KS DFT) is arguably the most widely applied electronic-structure method with tens of thousands publications each year in a wide variety fields. Its importance and usefulness can thus hardly be overstated. The central quantity that determines accuracy KS DFT calculations exchange-correlation functional. exact form unknown, or better "unknowable", therefore derivation ever more accurate yet efficiently applicable approximate functionals "holy grail" field. In this context, simultaneous minimization so-called delocalization errors static correlation greatest challenge needs to overcome as we move toward computationally efficient methods. many cases, an improvement on one these two aspects (also often termed fractional-charge fractional-spin errors, respectively) generates deterioration other one. Here report recent notable progress escaping "zero-sum-game" by constructing new based exact-exchange energy density. particular, local hybrid range-separated are discussed incorporate additional terms deal well errors. Taking hints from coordinate-space models nondynamical strong electron correlations (the B13 KP16/B13 models), position-dependent functions cover real space have been devised incorporated into local-mixing determining position-dependence admixture hybrids treatment range separation hybrids. While initial followed closely frameworks, meanwhile simpler real-space ratios semilocal densities found, providing basis for relatively simple numerically convenient functionals. Notably, correction either increase decrease locally (and interelectronic-distance space), leading even regions negative cases particularly correlations. Efficient implementations fast computer code (Turbomole) using seminumerical integration techniques make such promising tools complicated composite systems research areas, where simultaneously small crucial. First real-world application examples provided, including stretched bonds, symmetry-breaking hyperfine coupling open-shell transition-metal complexes, reduction computation nuclear shieldings magnetizabilities. newest versions (e.g., ωLH23tdE) retain excellent frontier-orbital energies correct asymptotic potential underlying ωLH22t while improving substantially strong-correlation cases. further linked performance impactful deep-neural-network "black-box" DM21, which itself may viewed hybrid.

Language: Английский

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Examining the Impact of Local Constraint Violations on Energy Computations in DFT

Journal of Computational Chemistry, Journal Year: 2025, Volume and Issue: 46(1)

Published: Jan. 2, 2025

ABSTRACT This work examines the impact of locally imposed constraints in Density Functional Theory (DFT). Using a metric referred to as extent violation index (EVI), we quantify how well exchange‐correlation functionals adhere local constraints. Applying EVIs diverse set molecules for GGA reveals constraint violations, particularly semi‐empirical functionals. We leverage explore potential connections between these violations and errors chemical properties. While no correlation is observed atomization energies, significant statistical emerges total energies. Similarly, analysis reaction energies suggests weak positive correlations specific However, definitive conclusions about error cancellation mechanisms cannot be made at this time. These observations revealed by may useful consideration when designing future generations semilocal

Language: Английский

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What Dictates the α-Effect in Gas-Phase S_N2 Reactions? A Density Functional Theory Study

The Journal of Physical Chemistry A, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 5, 2025

The α-effect is an important concept in chemistry and biochemistry, namely that for a bimolecular nucleophilic substitution (SN2) reaction, the nucleophilicity of atom increased if its adjacent (α) has lone pair electrons, lowering reaction barrier height increasing rate. However, exceptions exist, even very similar structural motifs. We investigate what underlies gas-phase SN2 reactions using two total energy decomposition schemes based on density functional theory (DFT) find steric effects play role, but there exists strong linear correlation between electrostatic contribution, suggesting it interaction stabilizes transition state leads to reactions. This multifaceted explanation resolves long-standing uncertainty about α-effect. show increases with branching central carbon atom.

Language: Английский

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Overview on Building Blocks and Applications of Efficient and Robust Extended Tight Binding

The Journal of Physical Chemistry A, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 27, 2025

The extended tight binding (xTB) family of methods opened many new possibilities in the field computational chemistry. Within just 5 years, GFN2-xTB parametrization for all elements up to Z = 86 enabled more than a thousand applications, which were previously not feasible with other electronic structure methods. xTB provide robust and efficient way apply quantum mechanics-based approaches obtaining molecular geometries, computing free energy corrections or describing noncovalent interactions found applicability targets. A crucial contribution success is availability within simulation packages frameworks, supported by open source development its program library packages. We present comprehensive summary applications capabilities different fields Moreover, we consider main software calculations, covering their current ecosystem, novel features, usage scientific community.

Language: Английский

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Function domains and the universal matrix functional of multi-state density functional theory

The Journal of Chemical Physics, Journal Year: 2025, Volume and Issue: 162(10)

Published: March 11, 2025

On the basis of recent advancements in Hamiltonian matrix density functional for multiple electronic eigenstates, this study delves into mathematical foundation multistate theory (MSDFT). We extend a number physical concepts at core Kohn–Sham DFT, such as representability, to functional. In work, we establish existence universal many states proper generalization Lieb ground state. Consequently, variation principle MSDFT can be rigorously defined within an appropriate domain densities, thereby providing solid framework DFT both state and excited states. further show that analytical structure is considerably constrained by subspace symmetry invariance properties, requiring ensuring all elements are variationally optimized coherent manner until spanned lowest eigenstates obtained. This work solidifies theoretical treat using theory.

Language: Английский

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