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Borocci S, Grandinetti F, Sanna N, Zazza C. Noble Gas Anions: An Overview of Strategies and Bonding Motifs. Chem Asian J 2024; 19:e202400191. [PMID: 38735841 DOI: 10.1002/asia.202400191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/30/2024] [Accepted: 05/09/2024] [Indexed: 05/14/2024]
Abstract
This review article aims to provide an overview of the strategies employed to prepare noble gas anions under different environments and experimental conditions, and of the bonding motifs typically occurring in these species. Observed systems include anions fixed into synthesized salts, detected in the gas phase or in high-pressure devices. The major role of the theoretical calculations is also highlighted, not only in support of the experiments, but also as effective in predicting still unreported species. The chemistry of noble gas anions overall appears as a varied and rich paint, offering fascinating opportunities for both experimentalists and theoreticians.
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Affiliation(s)
- Stefano Borocci
- Dipartimento per la Innovazione nei sistemi Biologici, Agroalimentari e Forestali (DIBAF), Università della Tuscia, L.go dell'Università, s.n.c., 01100, Viterbo, Italy
- Istituto per i Sistemi Biologici (ISB) del CNR, Sede di Roma -, Meccanismi di Reazione c/o Dipartimento di Chimica, Sapienza Università di Roma, P.le A. Moro 5, 00185, Rome, Italy
| | - Felice Grandinetti
- Dipartimento per la Innovazione nei sistemi Biologici, Agroalimentari e Forestali (DIBAF), Università della Tuscia, L.go dell'Università, s.n.c., 01100, Viterbo, Italy
- Istituto per i Sistemi Biologici (ISB) del CNR, Sede di Roma -, Meccanismi di Reazione c/o Dipartimento di Chimica, Sapienza Università di Roma, P.le A. Moro 5, 00185, Rome, Italy
| | - Nico Sanna
- Dipartimento per la Innovazione nei sistemi Biologici, Agroalimentari e Forestali (DIBAF), Università della Tuscia, L.go dell'Università, s.n.c., 01100, Viterbo, Italy
- Istituto per la Scienza e Tecnologia dei Plasmi (ISTP) del CNR, Via Amendola 122/D, 70126, Bari, Italy
| | - Costantino Zazza
- Dipartimento per la Innovazione nei sistemi Biologici, Agroalimentari e Forestali (DIBAF), Università della Tuscia, L.go dell'Università, s.n.c., 01100, Viterbo, Italy
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2
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Pizzi A, Dhaka A, Beccaria R, Resnati G. Anion⋯anion self-assembly under the control of σ- and π-hole bonds. Chem Soc Rev 2024; 53:6654-6674. [PMID: 38867604 DOI: 10.1039/d3cs00479a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
The electrostatic attraction between charges of opposite signs and the repulsion between charges of the same sign are ubiquitous and influential phenomena in recognition and self-assembly processes. However, it has been recently revealed that specific attractive forces between ions with the same sign are relatively common. These forces can be strong enough to overcome the Coulomb repulsion between ions with the same sign, leading to the formation of stable anion⋯anion and cation⋯cation adducts. Hydroden bonds (HBs) are probably the best-known interaction that can effectively direct these counterintuitive assembly processes. In this review we discuss how σ-hole and π-hole bonds can break the paradigm of electrostatic repulsion between like-charges and effectively drive the self-assembly of anions into discrete as well as one-, two-, or three-dimensional adducts. σ-Hole and π-hole bonds are the attractive forces between regions of excess electron density in molecular entities (e.g., lone pairs or π bond orbitals) and regions of depleted electron density that are localized at the outer surface of bonded atoms opposite to the σ covalent bonds formed by atoms (σ-holes) and above and below the planar portions of molecular entities (π-holes). σ- and π-holes can be present on many different elements of the p and d block of the periodic table and the self-assembly processes driven by their presence can thus involve a wide diversity of mono- and di-anions. The formed homomeric and heteromeric adducts are typically stable in the solid phase and in polar solvents but metastable or unstable in the gas phase. The pivotal role of σ- and π-hole bonds in controlling anion⋯anion self-assembly is described in key biopharmacological systems and in molecular materials endowed with useful functional properties.
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Affiliation(s)
- Andrea Pizzi
- NFMLab, Department of Chemistry, Materials, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, I-20131 Milano, Italy.
| | - Arun Dhaka
- NFMLab, Department of Chemistry, Materials, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, I-20131 Milano, Italy.
| | - Roberta Beccaria
- NFMLab, Department of Chemistry, Materials, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, I-20131 Milano, Italy.
| | - Giuseppe Resnati
- NFMLab, Department of Chemistry, Materials, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, I-20131 Milano, Italy.
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3
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Martín-Fernández C, Montero-Campillo MM, Alkorta I. Hydrogen Bonds Are Never of an "Anti-electrostatic" Nature: A Brief Tour of a Misleading Nomenclature. J Phys Chem Lett 2024; 15:4105-4110. [PMID: 38634115 PMCID: PMC11033937 DOI: 10.1021/acs.jpclett.4c00779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 04/02/2024] [Accepted: 04/03/2024] [Indexed: 04/19/2024]
Abstract
A large amount of scientific works have contributed through the years to rigorously reflect the different forces leading to the formation of hydrogen bonds, the electrostatic and polarization ones being the most important among them. However, we have witnessed lately with the emergence of a new terminology, anti-electrostatic hydrogen bonds (AEHBs), that seems to contradict this reality. This nomenclature is used in the literature to describe hydrogen bonds between equally charged systems to justify the existence of these species, despite numerous proofs showing that AEHBs are, as any other hydrogen bond between neutral species, mostly due to electrostatic forces. In this Viewpoint, we summarize the state of the art regarding this issue, try to explain why this terminology is very misleading, and strongly recommend avoiding its use based on the hydrogen bond physical grounds.
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Affiliation(s)
| | - M. Merced Montero-Campillo
- Departamento
de Química (Módulo 13, Facultad de Ciencias),
Campus de Excelencia UAM-CSIC, Universidad
Autónoma de Madrid, 28049 Madrid, Spain
| | - Ibon Alkorta
- Instituto
de Química Médica (CSIC), 28006 Madrid, Spain
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4
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Martín-Fernández C, Ferrer M, Alkorta I, Montero-Campillo MM, Elguero J, Mandado M. Metastable Charged Dimers in Organometallic Species: A Look into Hydrogen Bonding between Metallocene Derivatives. Inorg Chem 2023; 62:16523-16537. [PMID: 37755334 DOI: 10.1021/acs.inorgchem.3c02355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
Multiply charged complexes bound by noncovalent interactions have been previously described in the literature, although they were mostly focused on organic and main group inorganic systems. In this work, we show that similar complexes can also be found for organometallic systems containing transition metals and deepen in the reasons behind the existence of these species. We have studied the structures, binding energies, and dissociation profiles in the gas phase of a series of charged hydrogen-bonded dimers of metallocene (Ru, Co, Rh, and Mn) derivatives isoelectronic with the ferrocene dimer. Our results indicate that the carboxylic acid-containing dimers are more strongly bonded and present larger barriers to dissociation than the amide ones and that the cationic complexes tend to be more stable than the anionic ones. Additionally, we describe for the first time the symmetric proton transfer that can occur while in the metastable phase. Finally, we use a density-based energy decomposition analysis to shine light on the nature of the interaction between the dimers.
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Affiliation(s)
| | - Maxime Ferrer
- Instituto de Química Médica (CSIC), Juan de la Cierva, 3, 28006 Madrid, Spain
- PhD Programme in Theoretical Chemistry and Computational Modelling, Doctoral School, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Ibon Alkorta
- Instituto de Química Médica (CSIC), Juan de la Cierva, 3, 28006 Madrid, Spain
| | - M Merced Montero-Campillo
- Departamento de Química (Módulo 13, Facultad de Ciencias), Campus de Excelencia UAM-CSIC, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - José Elguero
- Instituto de Química Médica (CSIC), Juan de la Cierva, 3, 28006 Madrid, Spain
| | - Marcos Mandado
- Departamento de Química Física, Universidade de Vigo, Lagoas-Marcosende s/n, 36310 Vigo, Spain
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Guha AK. Can Dative Bond Between Two Anions Possible? Chemphyschem 2023; 24:e202300403. [PMID: 37450354 DOI: 10.1002/cphc.202300403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 07/10/2023] [Accepted: 07/14/2023] [Indexed: 07/18/2023]
Abstract
Formation of a genuine chemical bond between two similarly charged fragments is beyond expectation. Any such interaction generally lies in the realm of non-covalent interaction. Herein, formation of a strong dative covalent bond between two anionic fragments is reported for the first time. Calculation using ab initio coupled cluster theory reveals the formation of an unprecedented strong H3 Be- ←X- (X- =CH3 - , CN- , OH- , F- ) dative covalent bond. The calculated bond dissociation energies in polar solvents are significant, which indicates the possibility of their experimental realization.
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Affiliation(s)
- Ankur Kanti Guha
- Advanced Computational Chemistry Centre, Department of Chemistry, Cotton University Panbazar, Guwahati, Assam, 781001, India
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Scheiner S. Does a halogen bond require positive potential on the acid and negative potential on the base? Phys Chem Chem Phys 2023; 25:7184-7194. [PMID: 36815530 DOI: 10.1039/d3cp00379e] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
It is usually expected that formation of a halogen bond (XB) requires that a region of positive electrostatic potential associated with a σ or π-hole on the Lewis acid will interact with the negative potential of the base, either a lone pair or π-bond region. Quantum calculations of model systems suggest this not to be necessary. The placement of electron-withdrawing substituents on the base can reverse the sign of the potential in its lone pair or π-bond region to positive, and this base can nonetheless engage in a XB with the positive σ-hole of a Lewis acid. The reverse scenario is also possible in certain circumstances, as a negatively charged σ-hole can form a XB with the negative lone pair region of a base. Despite these classical Coulombic repulsions, the overall electrostatic interaction is attractive in these XBs, albeit only weakly so. The strengths of these bonds are surprisingly insensitive to changes in the partner molecule. For example, even a wide range in the depth of the σ-hole of the approaching acid yields only a minimal change in the strength of the XB to a base with a positive potential.
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Affiliation(s)
- Steve Scheiner
- Department of Chemistry and Biochemistry Utah State University Logan, Utah, USA, 84322-0300.
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Oliveira BGD. Why much of Chemistry may be indisputably non-bonded? SEMINA: CIÊNCIAS EXATAS E TECNOLÓGICAS 2023. [DOI: 10.5433/1679-0375.2022v43n2p211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In this compendium, the wide scope of all intermolecular interactions ever known has been revisited, in particular giving emphasis the capability of much of the elements of the periodic table to form non-covalent contacts. Either hydrogen bonds, dihydrogen bonds, halogen bonds, pnictogen bonds, chalcogen bonds, triel bonds, tetrel bonds, regium bonds, spodium bonds or even the aerogen bond interactions may be cited. Obviously that experimental techniques have been used in some works, but it was through the theoretical methods that these interactions were validate, wherein the QTAIM integrations and SAPT energy partitions have been useful in this regard. Therefore, the great goal concerns to elucidate the interaction strength and if the intermolecular system shall be total, partial or non-covalently bonded, wherein this last one encompasses the most majority of the intermolecular interactions what leading to affirm that chemistry is debatably non-bonded.
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The Role of Hydrogen Bonds in Interactions between [PdCl 4] 2- Dianions in Crystal. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27072144. [PMID: 35408543 PMCID: PMC9000617 DOI: 10.3390/molecules27072144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/18/2022] [Accepted: 03/22/2022] [Indexed: 11/17/2022]
Abstract
[PdCl4]2- dianions are oriented within a crystal in such a way that a Cl of one unit approaches the Pd of another from directly above. Quantum calculations find this interaction to be highly repulsive with a large positive interaction energy. The placement of neutral ligands in their vicinity reduces the repulsion, but the interaction remains highly endothermic. When the ligands acquire a unit positive charge, the electrostatic component and the full interaction energy become quite negative, signalling an exothermic association. Raising the charge on these counterions to +2 has little further stabilizing effect, and in fact reduces the electrostatic attraction. The ability of the counterions to promote the interaction is attributed in part to the H-bonds which they form with both dianions, acting as a sort of glue.
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Weinhold F. Anti-Electrostatic Pi-Hole Bonding: How Covalency Conquers Coulombics. Molecules 2022; 27:377. [PMID: 35056689 PMCID: PMC8780338 DOI: 10.3390/molecules27020377] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 12/30/2021] [Accepted: 12/30/2021] [Indexed: 12/20/2022] Open
Abstract
Intermolecular bonding attraction at π-bonded centers is often described as "electrostatically driven" and given quasi-classical rationalization in terms of a "pi hole" depletion region in the electrostatic potential. However, we demonstrate here that such bonding attraction also occurs between closed-shell ions of like charge, thereby yielding locally stable complexes that sharply violate classical electrostatic expectations. Standard DFT and MP2 computational methods are employed to investigate complexation of simple pi-bonded diatomic anions (BO-, CN-) with simple atomic anions (H-, F-) or with one another. Such "anti-electrostatic" anion-anion attractions are shown to lead to robust metastable binding wells (ranging up to 20-30 kcal/mol at DFT level, or still deeper at dynamically correlated MP2 level) that are shielded by broad predissociation barriers (ranging up to 1.5 Å width) from long-range ionic dissociation. Like-charge attraction at pi-centers thereby provides additional evidence for the dominance of 3-center/4-electron (3c/4e) nD-π*AX interactions that are fully analogous to the nD-σ*AH interactions of H-bonding. Using standard keyword options of natural bond orbital (NBO) analysis, we demonstrate that both n-σ* (sigma hole) and n-π* (pi hole) interactions represent simple variants of the essential resonance-type donor-acceptor (Bürgi-Dunitz-type) attraction that apparently underlies all intermolecular association phenomena of chemical interest. We further demonstrate that "deletion" of such π*-based donor-acceptor interaction obliterates the characteristic Bürgi-Dunitz signatures of pi-hole interactions, thereby establishing the unique cause/effect relationship to short-range covalency ("charge transfer") rather than envisioned Coulombic properties of unperturbed monomers.
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Affiliation(s)
- Frank Weinhold
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53705, USA
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Abstract
A halogen-bonded complex containing a pair of anions can be made more stable than the isolated anions if the Lewis acid is a long carbon chain, fully substituted by CN groups, with an I atom on one end and a COO− group on the other, with Cl− as base.
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Affiliation(s)
- Steve Scheiner
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0300, USA
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Zierkiewicz W, Michalczyk M, Maris T, Wysokiński R, Scheiner S. Experimental and theoretical evidence of attractive interactions between dianions: [PdCl 4] 2-⋯[PdCl 4] 2. Chem Commun (Camb) 2021; 57:13305-13308. [PMID: 34807208 DOI: 10.1039/d1cc05640a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Inspection of the arrangement of tetrachloridopalladate(II) centers in a crystalline solid places the Cl of one [PdCl4]2- directly above the Pd center of its neighbor. A survey of the CSD provides 22 more examples of such MX42-⋯MX42- complexes, with M being a Group 10 metal and X = Cl, Br, or I. Quantum calculations attribute this arrangement to a π-hole bond wherein Cl lone pairs of one unit transfer charge to vacant orbitals above the Pd center of its neighbor. The stabilizing effect of this bond must overcome the strong Coulombic repulsion between the two dianions, which is facilitated by a polarizable environment as would be present in a crystal, but much more so when the effects of the neighboring counterions are factored in. These conclusions are extended to other [MX4]2- homodimers, where M represents other members of Group 10, namely Ni and Pt.
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Affiliation(s)
- Wiktor Zierkiewicz
- Faculty of Chemistry Wrocław University of Science and Technology Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Mariusz Michalczyk
- Faculty of Chemistry Wrocław University of Science and Technology Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Thierry Maris
- Département de Chimie, Université de Montréal, Montréal, Québec, H3C 3J7, Canada
| | - Rafał Wysokiński
- Faculty of Chemistry Wrocław University of Science and Technology Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Steve Scheiner
- Department of Chemistry and Biochemistry Utah State University, Logan, Utah 84322-0300, USA
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Daolio A, Pizzi A, Terraneo G, Frontera A, Resnati G. Anion⋅⋅⋅Anion Interactions Involving σ-Holes of Perrhenate, Pertechnetate and Permanganate Anions. Chemphyschem 2021; 22:2281-2285. [PMID: 34541753 PMCID: PMC9291842 DOI: 10.1002/cphc.202100681] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Indexed: 01/14/2023]
Abstract
In this communication experimental and theoretical results are reported affording strong evidence that interactions between electron rich atoms and the metal of tetroxide anions of group 7 elements are a new case of attractive and σ‐hole interactions. Single crystal X‐ray analyses, molecular electrostatic potentials, quantum theory of atoms‐in‐molecules, and noncovalent interaction plot analyses show that in crystalline permanganate and perrhenate salts the metal in Mn/ReO4− anion can act as electron acceptors, the oxygen of another Mn/ReO4− anion can act as the donor and supramolecular anionic dimers or polymers are formed. The name matere bond (MaB) is proposed to categorize these noncovalent interactions and to differentiate them from the classical metal‐ligand coordination bond.
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Affiliation(s)
- Andrea Daolio
- Department of Chemistry, Materials and, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, 20131, Milano, Italy
| | - Andrea Pizzi
- Department of Chemistry, Materials and, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, 20131, Milano, Italy
| | - Giancarlo Terraneo
- Department of Chemistry, Materials and, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, 20131, Milano, Italy
| | - Antonio Frontera
- Department of Chemistry, Universitat de les Illes Balears, Crta. de Valldemossa, 07122, Palma de Mallorca, Baleares, Spain
| | - Giuseppe Resnati
- Department of Chemistry, Materials and, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, 20131, Milano, Italy
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Michalczyk M, Zierkiewicz W, Wysokiński R, Scheiner S. Triel bonds within anion ···anion complexes. Phys Chem Chem Phys 2021; 23:25097-25106. [PMID: 34751289 DOI: 10.1039/d1cp04296c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The ability of two anions to interact with one another is tested in the context of pairs of TrX4- homodimers, where Tr represents any of the triel atoms B, Al, Ga, In, or Tl, and X refers to a halogen substituent F, Cl, or Br. None of these pairs engage in a stable complex in the gas phase, but the situation reverses in water where the two monomers are held together by Tr⋯X triel bonds, complemented by stabilizing interactions between X atoms. Some of these bonds are quite strong, notably those involving TrF4-, with interaction energies surpassing 30 kcal mol-1. Others are very much weaker, with scarcely exothermic binding energies. The highly repulsive electrostatic interactions are counteracted by large polarization energies.
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Affiliation(s)
- Mariusz Michalczyk
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Wiktor Zierkiewicz
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Rafał Wysokiński
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Steve Scheiner
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0300, USA.
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Wysokiński R, Zierkiewicz W, Michalczyk M, Scheiner S. Ability of Lewis Acids with Shallow σ-Holes to Engage in Chalcogen Bonds in Different Environments. Molecules 2021; 26:molecules26216394. [PMID: 34770803 PMCID: PMC8586936 DOI: 10.3390/molecules26216394] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 10/19/2021] [Accepted: 10/21/2021] [Indexed: 11/16/2022] Open
Abstract
Molecules of the type XYT = Ch (T = C, Si, Ge; Ch = S, Se; X,Y = H, CH3, Cl, Br, I) contain a σ-hole along the T = Ch bond extension. This hole can engage with the N lone pair of NCH and NCCH3 so as to form a chalcogen bond. In the case of T = C, these bonds are rather weak, less than 3 kcal/mol, and are slightly weakened in acetone or water. They owe their stability to attractive electrostatic energy, supplemented by dispersion, and a much smaller polarization term. Immersion in solvent reverses the electrostatic interaction to repulsive, while amplifying the polarization energy. The σ-holes are smaller for T = Si and Ge, even negative in many cases. These Lewis acids can nonetheless engage in a weak chalcogen bond. This bond owes its stability to dispersion in the gas phase, but it is polarization that dominates in solution.
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Affiliation(s)
- Rafał Wysokiński
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland;
- Correspondence: (R.W.); (W.Z.); (S.S.)
| | - Wiktor Zierkiewicz
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland;
- Correspondence: (R.W.); (W.Z.); (S.S.)
| | - Mariusz Michalczyk
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland;
| | - Steve Scheiner
- Department of Chemistry and Biochemistry, Utah State University, Logan, UT 84322-0300, USA
- Correspondence: (R.W.); (W.Z.); (S.S.)
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