Atoms in molecules in real space: a fertile field for chemical bonding

Physical Chemistry Chemical Physics, Journal Year: 2023, Volume and Issue: 25(15), P. 10231 - 10262

Published: Jan. 1, 2023

In this Perspective we review some recent advances in the concept of atoms-in-molecules from a real space perspective.

Language: Английский

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The Halogen Bond in Weakly Bonded Complexes and the Consequences for Aromaticity and Spin-Orbit Coupling

Molecules, Journal Year: 2023, Volume and Issue: 28(2), P. 772 - 772

Published: Jan. 12, 2023

The halogen bond complexes CF3X⋯Y and C2F3X⋯Y, with Y = furan, thiophene, selenophene X Cl, Br, I, have been studied by using DFT CCSD(T) in order to understand which factors govern the interaction between atom aromatic ring. We found that PBE0-dDsC/QZ4P gives an adequate description of energies these complexes, compared experimental results. π-bonds perpendicular orientation is stronger than in-plane lone pairs heteroatom cycle. strength follows trend Cl < Br I; chalcogenide ring nor hybridization C−X play a decisive role. energy decomposition analysis shows dominated all three contributions, viz., electrostatic, orbital, dispersion interactions: not one factor dominates energy. aromaticity undisturbed upon formation: π-ring current remains equally strong diatropic complex as it for free However, spin-orbit coupling singlet triplet π→π* states increased formation faster intersystem crossing therefore expected.

Language: Английский

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Role of Charge Transfer in Halogen Bonding

The Journal of Physical Chemistry A, Journal Year: 2021, Volume and Issue: 125(14), P. 2944 - 2953

Published: April 2, 2021

Halogen bonding has received intensive attention recently for its applications in the construction of supramolecular assemblies and crystal engineering implications potentials chemical biological processes rational drug design. Peculiarly, intermolecular interactions, halogen atoms are known as electron-donating groups carrying partial negative charges molecules due to high electronegativity, but they can counterintuitively act Lewis acids bind with bases form a bond. The unsettling issue regarding nature is whether electrostatics or charge transfer interaction dominates. proposed σ-hole concept nicely reinforces role electrostatic attraction. Also, good correlations between strength energy from simple point-charge model have been found. This leads claim that there no need invoke But alternative evidence supporting importance interaction. Here, we visited series prominent bonded complexes types Y3C–X···Z (X = Br, I; Y F, Cl, Br; Z F–, Cl–, Br–, I–, NMe3) block-localized wave function (BLW) method at M06-2X-D3/6-311+G(d,p) (def2-SVP iodine) level theory. As simplest variant ab initio valence bond (VB) theory, BLW unique strict localization electrons within interacting moieties, allowing quantitative evaluation effect on geometries, spectral properties, energetics complexes. By comparing without interaction, proved significantly shortens X···Z distance stretches C–X bonds. shortening results less favorable steric effect, which composed Pauli repulsion, electrostatics, electron correlation. There approximate linear binding energy. These may lead illusion unimportant irrelevant, further analyses showed inclusion critical proper description bonding, considering only polarization about 45–60% strengths much elongated distances.

Language: Английский

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“Anti‐electrostatic” Halogen Bonding between Ions of Like Charge

Chemistry - A European Journal, Journal Year: 2021, Volume and Issue: 27(67), P. 16530 - 16542

Published: Aug. 19, 2021

Abstract Halogen bonding occurs between molecules featuring Lewis acidic halogen substituents and bases. It is often rationalized as a predominantly electrostatic interaction thus interactions ions of like charge (e. g., anionic bond donors with halides) seem counter‐intuitive. Herein, we provide an overview on such complexes. First, theoretical studies are described their findings compared. Next, experimental evidences presented in the form crystal structure database analyses, recent examples strong “anti‐electrostatic” crystals, observation also solution. We then compare these complexes to select “counter‐intuitive” adducts formed by other interactions, hydrogen bonding. Finally, comment key differences charge‐transfer polarization.

Language: Английский

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Current developments and trends in quantum crystallography

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials, Journal Year: 2024, Volume and Issue: 80(4), P. 249 - 274

Published: June 18, 2024

Quantum crystallography is an emerging research field of science that has its origin in the early days quantum physics and modern when it was almost immediately envisaged X-ray radiation could be somehow exploited to determine electron distribution atoms molecules. Today can seen as a composite area at intersection crystallography, chemistry, solid-state physics, applied mathematics computer science, with goal investigating problems, phenomena features crystalline state. In this article, state-of-the-art will described by presenting developments applications novel techniques have been introduced last 15 years. The focus on advances framework multipole model strategies, wavefunction-/density matrix-based approaches chemical topological techniques. Finally, possible future improvements expansions discussed, also considering new experimental computational technologies.

Language: Английский

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Halide Anions as Halogen Bond Acceptors

Crystal Growth & Design, Journal Year: 2025, Volume and Issue: unknown

Published: May 21, 2025

Language: Английский

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Decorated crown ethers as selective ion traps: Solvent’s role in crown’s preference towards a specific ion

Journal of Molecular Liquids, Journal Year: 2023, Volume and Issue: 381, P. 121791 - 121791

Published: April 6, 2023

Language: Английский

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Supramolecular Dimer as High-Performance pH Probe: Study on the Fluorescence Properties of Halogenated Ligands in Rigid Schiff Base Complex

International Journal of Molecular Sciences, Journal Year: 2023, Volume and Issue: 24(11), P. 9480 - 9480

Published: May 30, 2023

The development of high-performance fluorescence probes has been an active area research. In the present work, two new pH sensors Zn-3,5-Cl-saldmpn and Zn-3,5-Br-saldmpn based on a halogenated Schiff ligand (3,5-Cl-saldmpn = N, N'-(3,3'-dipropyhnethylamine) bis (3,5-chlorosalicylidene)) with linearity high signal-to-noise ratio were developed. Analyses revealed exponential intensification in their emission discernible chromatic shift upon increase from 5.0 to 7.0. could retain over 95% initial signal amplitude after 20 operational cycles, demonstrating excellent stability reversibility. To elucidate unique response, non-halogenated analog was introduced for comparison. structural optical characterization suggested that introduction halogen atoms can create additional interaction pathways between adjacent molecules enhance strength interaction, which not only improves but also forms long-range process formation aggregation state, thus enhancing response range. Meanwhile, above proposed mechanism verified by theoretical calculations.

Language: Английский

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Halogen bonding and mechanochemistry combined: synthesis, characterization, and application of N-iodosaccharin pyridine complexes

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 11(3), P. 781 - 795

Published: Dec. 5, 2023

Triturating N -iodosaccharin with electron-donating 4-substituted pyridines leads to either charge-neutral XB or cationic iodine( i ) complexes, offering promising alternatives the ubiquitous Barluenga's reagent as electrophilic iodination reagents.

Language: Английский

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Boat and Chair Shaped Hexahalogen Synthons

Chemistry - An Asian Journal, Journal Year: 2023, Volume and Issue: 18(6)

Published: Jan. 30, 2023

Non-covalent halogen bonding interactions are quintessential in crystal engineering for the construction of distinctive supramolecular synthons. Here, we report first crystalline evidences unique boat and chair shaped cyclic hexahalogen synthons structures α,α,α',α',4-pentabromo-o-xylene (PBX) α,α,α',α',4,5-hexabromo-o-xylene (HBX) respectively. Nature stability constituent scrutinized with help quantum-chemical calculations. Pendás' interacting quantum atoms approach confirmed Br⋅⋅⋅Br leading to major contribution from exchange-correlation. Although both molecules achiral nature, packing forces guide PBX crystallize chiral space group P21 a helix-like orientation while HBX packs centrosymmetric /n group. The extended furcations pentabromo derivative construct molecular framework consisting macrocycles realized through bonding.

Language: Английский

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