The Nature of Hydrogen Bonds: A Delineation of the Role of Different Energy Components on Hydrogen Bond Strengths and Lengths

Chemistry - An Asian Journal, Journal Year: 2019, Volume and Issue: 14(16), P. 2760 - 2769

Published: June 26, 2019

Hydrogen bonds are a complex interplay between different energy components, and their nature is still subject of an ongoing debate. In this minireview, we therefore provide overview the perspectives on hydrogen bonding. This will be done by discussing following individual components: 1) electrostatic interactions, 2) charge-transfer 3) π-resonance assistance, 4) steric repulsion, 5) cooperative effects, 6) dispersion interactions 7) secondary interactions. We demonstrate how these energetic factors essential in correct description bond, discuss several examples systems whose geometrical features not captured easy-to-use predictive models.

Language: Английский

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Non-covalent interactions from a Quantum Chemical Topology perspective

Journal of Molecular Modeling, Journal Year: 2022, Volume and Issue: 28(9)

Published: Aug. 25, 2022

Abstract About half a century after its little-known beginnings, the quantum topological approach called QTAIM has grown into widespread, but still not mainstream, methodology of interpretational chemistry. Although often confused in textbooks with yet another population analysis, be it perhaps an elegant somewhat esoteric one, been enriched about dozen other research areas sharing main mathematical language, such as Interacting Quantum Atoms (IQA) or Electron Localisation Function (ELF), to form overarching Chemical Topology (QCT). Instead reviewing latter’s role understanding non-covalent interactions, we propose number ideas emerging from full consequences space-filling nature atoms, and discuss how they (will) impact on interatomic including ones. The architecture force field FFLUX, which is based these ideas, outlined. A new method Relative Energy Gradient (REG) put forward, able, by computation, detect fragments given molecular assembly govern energetic behaviour this whole assembly. This can offer insight typical balance competing atomic energies both covalent case studies. brief discussion so-called bond critical points given, highlighting concerns their meaning, mainly arena interactions.

Language: Английский

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On the strength of hydrogen bonding within water clusters on the coordination limit

Journal of Computational Chemistry, Journal Year: 2020, Volume and Issue: 41(26), P. 2266 - 2277

Published: Aug. 6, 2020

Hydrogen bonds (HB) are arguably the most important noncovalent interactions in chemistry. We study herein how differences connectivity alter strength of HBs within water clusters different sizes. used for this purpose interacting quantum atoms energy partition, which allows quantification HB formation energies a molecular cluster. could expand our previously reported hierarchy these systems (Phys. Chem. Phys., 2016, 18, 19557) to include tetracoordinated monomers. Surprisingly, between molecules not strongest despite widespread occurrence motifs (e.g., ice Ih ). The H2 O involve tricoordinated Nonetheless, tetracoordination is preferred large because (a) it reduces anticooperativity associated with double donors and acceptors (b) results larger number favorable system. Finally, we also discuss importance exchange-correlation discriminate among examined types clusters, use above-mentioned scale quickly assess relative stability isomers given cluster, (c) findings research can be exploited indagate about polymorphs crystallography. Overall, expect that investigation will provide valuable insights into subtle interplay tri- as well ensuing interaction clusters.

Language: Английский

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Cooperativity and Anticooperativity in Ion‐Water Interactions: Implications for the Aqueous Solvation of Ions

ChemPhysChem, Journal Year: 2021, Volume and Issue: 22(12), P. 1269 - 1285

Published: Feb. 26, 2021

Non-additive effects in hydrogen bonds (HB) take place as a consequence of electronic charge transfers. Therefore, it is natural to expect cooperativity and anticooperativity ion-water interactions. Nevertheless, investigations on this matter are scarce. This paper addresses the interactions (i) cations Li+ , Na+ K+ Be2+ Mg2+ Ca2+ together with (ii) anions F- Cl- Br- NO3- SO42- water clusters (H2 O)n n=1-8, these ions HBs within complete molecular adducts. We used quantum chemical topology tools, specifically theory atoms molecules interacting energy partition investigate non-additive among studied herein. Our results show decrease interaction between first neighbouring an increment coordination number. also found strong cooperative interplay ion-dipole systems. Such affects considerably their second solvation shells aqueous environments. Overall, we believe article provides valuable information about how contacts interact each other they relate interactions, such HBs, framework media.

Language: Английский

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An Interacting Quantum Atoms (IQA) and Relative Energy Gradient (REG) Study of the Halogen Bond with Explicit Analysis of Electron Correlation

Molecules, Journal Year: 2020, Volume and Issue: 25(11), P. 2674 - 2674

Published: June 9, 2020

Energy profiles of seven halogen-bonded complexes were analysed with the topological energy partitioning called Interacting Quantum Atoms (IQA) at MP4(SDQ)/6–31 + G(2d,2p) level theory. Explicit interatomic electron correlation energies are included in analysis. Four combine X2 (X = Cl or F) HCN NH3, while remaining three ClF HCN, NH3 N2. Each complex was systematically deformed by translating constituent molecules along its central axis linking X and N, reoptimising geometry. The Relative Gradient (REG) method (Theor. Chem. Acc. 2017, 136, 86) then computes which IQA most correlate total during process formation further compression beyond respective equilibrium geometries. It turns out that covalent (i.e., exchange) halogen bond, X…N, itself drives formation. When compressed from their to shorter X…N distance intra-atomic N is charge. REG analysis restricted between again formation, best described destabilisation through-space “outer” halogen.

Language: Английский

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Tuning the Binding Strength of Even and Uneven Hydrogen-Bonded Arrays with Remote Substituents

The Journal of Physical Chemistry A, Journal Year: 2020, Volume and Issue: 124(45), P. 9451 - 9463

Published: Oct. 15, 2020

We investigated the tunability of hydrogen bond strength by altering charge accumulation around frontier atoms with remote substituents. For pyridine···H2O NH2 and CN substituted at different positions on pyridine, we find that electron-withdrawing group decreases negative atom N, resulting in weakening bond, whereas electron-donating increases strengthening bond. By applying these design principles DDAA–AADD, DADA–ADAD, DAA–ADD, ADA–DAD hydrogen-bonded dimers, effect substituent is delocalized over whole molecular system. As a consequence, systems an equal number donor (D) acceptor (A) are not tunable predictable way because cancellation counteracting effects. Furthermore, show position long-range electrostatics can play important role as well. Overall, presented this work suitable for monomers unequal be exploited to tune binding supramolecular building blocks.

Language: Английский

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Attractive acceptor-acceptor interactions in self-complementary quadruple hydrogen bonds for molecular self-assembly

Physical Chemistry Chemical Physics, Journal Year: 2024, Volume and Issue: 26(37), P. 24470 - 24476

Published: Jan. 1, 2024

Molecular self-assembly provides the means for creating large supramolecular structures, extending beyond capability of standard chemical synthesis. To harness power self-assembly, it is necessary to understand its driving forces. A potent method exploit self-complementary hydrogen bonding, where a molecule interacts with own copy by suitable positions hydrogen-bond donor (D) and acceptor (A) groups. With four bonds, there are two possible self complementary patterns: DDAA/AADD DADA/ADAD motifs. Of these, DDAA pattern usually more stable. The traditional explanation assumes that secondary interactions between equal groups, is, donors (D⋯D) or acceptors (A⋯A), repulsive. arrays would then have two, DADA six repulsive interactions. Here, using high-end quantum analysis, we show contrary explanation, A⋯A are, in fact, attractive. We revise model accordingly.

Language: Английский

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Hydroboration of imines: intermolecularvs.intramolecular hydride transfer

New Journal of Chemistry, Journal Year: 2023, Volume and Issue: 47(24), P. 11544 - 11556

Published: Jan. 1, 2023

We performed a detailed experimental and theoretical analysis of the 1,3-hydride shift in imine–BH 3 adducts, which represents crucial step formation mono-aminoboranes (R 2 N–BH ).

Language: Английский

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Reactivity of α,ω-Dihydrofluoropolyethers toward OH Predicted by Multiconformer Transition State Theory and the Interacting Quantum Atoms Approach

The Journal of Physical Chemistry A, Journal Year: 2020, Volume and Issue: 124(17), P. 3460 - 3470

Published: April 3, 2020

We report rate constants for the tropospheric reaction between OH radical and α,ω-dihydrofluoropolyethers, which represent a specific class of hydrofluoropolyethers family with formula HF2C(OCF2CF2)p(OCF2)qOCF2H. Four cases were considered: p0q2, p0q3, p1q0, p1q1 (pxqy denoting p = x q y) calculations performed by cost-effective protocol developed bimolecular hydrogen-abstraction reactions. This is based on multiconformer transition state theory relies computationally accessible M08-HX/apcseg-2//M08-HX/pcseg-1 calculations. Within protocol's approximations, results show that (1) calculated are within factor five experimental (p1q0 p1q1) (2) chain length composition have negligible effect constants, consistent work. The interacting quantum atoms energy decomposition scheme used to analyze observed trends extract chemical information related imaginary frequencies barrier heights key parameters controlling reactivity reaction. intramolecular exchange-correlation contributions in reactants states found be dominating factor.

Language: Английский

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A relative energy gradient (REG) study of the nitrogen inversion in N-substituted aziridines

Chemical Physics Letters, Journal Year: 2020, Volume and Issue: 758, P. 137927 - 137927

Published: Aug. 26, 2020

Language: Английский

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