E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Special Issue "Tetrel Bonds"

A special issue of Molecules (ISSN 1420-3049).

Deadline for manuscript submissions: 30 November 2018

Special Issue Editor

Guest Editor
Prof. Dr. Steve Scheiner

Department of Chemistry and Biochemistry, Utah State University, Logan, UT, USA
Website | E-Mail
Interests: noncovalent forces; H-bonds; computational chemistry

Special Issue Information

Dear Colleagues,

The replacement of the bridging H atom in H-bonds by a multitude of other, more electronegative, atoms has led to rapidly-increasing study of related noncovalent bonds, generally known as halogen, chalcogen, and pnicogen bonds. It has recently been recognized that elements of the tetrel family (C, Si, Ge, Sn, Pb) also engage in such bonds, wherein the tetrel atom serves as electron acceptor to an incoming Lewis base, and that these bonds can be quite strong. This Special Issue will delve into the many facets of tetrel bonds: The factors determining their strength, their geometrical requirements, various phenomena in which they play an outsized role, and the means by which they can be detected and measured.

Prof. Dr. Steve Scheiner
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Molecules is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1800 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • noncovalent bond
  • sigma-hole
  • charge transfer
  • molecular electrostatic potential

Published Papers (8 papers)

View options order results:
result details:
Displaying articles 1-8
Export citation of selected articles as:

Research

Open AccessArticle Strong Tetrel Bonds: Theoretical Aspects and Experimental Evidence
Molecules 2018, 23(10), 2642; https://doi.org/10.3390/molecules23102642 (registering DOI)
Received: 25 September 2018 / Revised: 4 October 2018 / Accepted: 5 October 2018 / Published: 15 October 2018
PDF Full-text (3288 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In recent years, noncovalent interactions involving group-14 elements of the periodic table acting as a Lewis acid center (or tetrel-bonding interactions) have attracted considerable attention due to their potential applications in supramolecular chemistry, material science and so on. The aim of the present
[...] Read more.
In recent years, noncovalent interactions involving group-14 elements of the periodic table acting as a Lewis acid center (or tetrel-bonding interactions) have attracted considerable attention due to their potential applications in supramolecular chemistry, material science and so on. The aim of the present study is to characterize the geometry, strength and bonding properties of strong tetrel-bond interactions in some charge-assisted tetrel-bonded complexes. Ab initio calculations are performed, and the results are supported by the quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) approaches. The interaction energies of the anionic tetrel-bonded complexes formed between XF3M molecule (X=F, CN; M=Si, Ge and Sn) and A anions (A=F, Cl, Br, CN, NC and N3) vary between −16.35 and −96.30 kcal/mol. The M atom in these complexes is generally characterized by pentavalency, i.e., is hypervalent. Moreover, the QTAIM analysis confirms that the anionic tetrel-bonding interaction in these systems could be classified as a strong interaction with some covalent character. On the other hand, it is found that the tetrel-bond interactions in cationic tetrel-bonded [p-NH3(C6H4)MH3]+···Z and [p-NH3(C6F4)MH3]+···Z complexes (M=Si, Ge, Sn and Z=NH3, NH2CH3, NH2OH and NH2NH2) are characterized by a strong orbital interaction between the filled lone-pair orbital of the Lewis base and empty BD*M-C orbital of the Lewis base. The substitution of the F atoms in the benzene ring provides a strong orbital interaction, and hence improved tetrel-bond interaction. For all charge-assisted tetrel-bonded complexes, it is seen that the formation of tetrel-bond interaction is accompanied bysignificant electron density redistribution over the interacting subunits. Finally, we provide some experimental evidence for the existence of such charge-assisted tetrel-bond interactions in crystalline phase. Full article
(This article belongs to the Special Issue Tetrel Bonds)
Figures

Graphical abstract

Open AccessArticle An Ab Initio Investigation of the Geometries and Binding Strengths of Tetrel-, Pnictogen-, and Chalcogen-Bonded Complexes of CO2, N2O, and CS2 with Simple Lewis Bases: Some Generalizations
Molecules 2018, 23(9), 2250; https://doi.org/10.3390/molecules23092250
Received: 20 August 2018 / Revised: 29 August 2018 / Accepted: 30 August 2018 / Published: 4 September 2018
PDF Full-text (2496 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Geometries, equilibrium dissociation energies (De), and intermolecular stretching, quadratic force constants (kσ) are presented for the complexes B⋯CO2, B⋯N2O, and B⋯CS2, where B is one of the following Lewis bases: CO,
[...] Read more.
Geometries, equilibrium dissociation energies (De), and intermolecular stretching, quadratic force constants (kσ) are presented for the complexes B⋯CO2, B⋯N2O, and B⋯CS2, where B is one of the following Lewis bases: CO, HCCH, H2S, HCN, H2O, PH3, and NH3. The geometries and force constants were calculated at the CCSD(T)/aug-cc-pVTZ level of theory, while generation of De employed the CCSD(T)/CBS complete basis-set extrapolation. The non-covalent, intermolecular bond in the B⋯CO2 complexes involves the interaction of the electrophilic region around the C atom of CO2 (as revealed by the molecular electrostatic surface potential (MESP) of CO2) with non-bonding or π-bonding electron pairs of B. The conclusions for the B⋯N2O series are similar, but with small geometrical distortions that can be rationalized in terms of secondary interactions. The B⋯CS2 series exhibits a different type of geometry that can be interpreted in terms of the interaction of the electrophilic region near one of the S atoms and centered on the C axis of CS2 (as revealed by the MESP) with the n-pairs or π-pairs of B. The tetrel, pnictogen, and chalcogen bonds so established in B⋯CO2, B⋯N2O, and B⋯CS2, respectively, are rationalized in terms of some simple, electrostatically based rules previously enunciated for hydrogen- and halogen-bonded complexes, B⋯HX and B⋯XY. It is also shown that the dissociation energy De is directly proportional to the force constant kσ, with a constant of proportionality identical within experimental error to that found previously for many B⋯HX and B⋯XY complexes. Full article
(This article belongs to the Special Issue Tetrel Bonds)
Figures

Graphical abstract

Open AccessFeature PaperArticle Tetrel Bonding Interactions in Perchlorinated Cyclopenta- and Cyclohexatetrelanes: A Combined DFT and CSD Study
Molecules 2018, 23(7), 1770; https://doi.org/10.3390/molecules23071770
Received: 3 July 2018 / Revised: 15 July 2018 / Accepted: 15 July 2018 / Published: 19 July 2018
Cited by 1 | PDF Full-text (2473 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In this manuscript, we combined DFT calculations (PBE0-D3/def2-TZVP level of theory) and a Cambridge Structural Database (CSD) survey to evaluate the ability of perchlorinated cyclopenta- and cyclohexatetrelanes in establishing tetrel bonding interactions. For this purpose, we used Tr5Cl10 and Tr
[...] Read more.
In this manuscript, we combined DFT calculations (PBE0-D3/def2-TZVP level of theory) and a Cambridge Structural Database (CSD) survey to evaluate the ability of perchlorinated cyclopenta- and cyclohexatetrelanes in establishing tetrel bonding interactions. For this purpose, we used Tr5Cl10 and Tr6Cl12 (Tr = Si and Ge) and HCN, HF, OH and Cl as electron donor entities. Furthermore, we performed an Atoms in Molecules (AIM) analysis to further describe and characterize the interactions studied herein. A survey of crystal structures in the CSD reveals that close contacts between Si and lone-pair-possessing atoms are quite common and oriented along the extension of the covalent bond formed by the silicon with the halogen atom. Full article
(This article belongs to the Special Issue Tetrel Bonds)
Figures

Graphical abstract

Open AccessFeature PaperArticle Comparative Strengths of Tetrel, Pnicogen, Chalcogen, and Halogen Bonds and Contributing Factors
Molecules 2018, 23(7), 1681; https://doi.org/10.3390/molecules23071681
Received: 29 June 2018 / Revised: 8 July 2018 / Accepted: 9 July 2018 / Published: 10 July 2018
Cited by 1 | PDF Full-text (1916 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Ab initio calculations are employed to assess the relative strengths of various noncovalent bonds. Tetrel, pnicogen, chalcogen, and halogen atoms are represented by third-row atoms Ge, As, Se, and Br, respectively. Each atom was placed in a series of molecular bonding situations, beginning
[...] Read more.
Ab initio calculations are employed to assess the relative strengths of various noncovalent bonds. Tetrel, pnicogen, chalcogen, and halogen atoms are represented by third-row atoms Ge, As, Se, and Br, respectively. Each atom was placed in a series of molecular bonding situations, beginning with all H atoms, then progressing to methyl substitutions, and F substituents placed in various locations around the central atom. Each Lewis acid was allowed to engage in a complex with NH3 as a common nucleophile, and the strength and other aspects of the dimer were assessed. In the context of fully hydrogenated acids, the strengths of the various bonds varied in the pattern of chalcogen > halogen > pnicogen ≈ tetrel. Methyl substitution weakened all bonds, but not in a uniform manner, resulting in a greatly weakened halogen bond. Fluorosubstitution strengthened the interactions, increasing its effect as the number of F atoms rises. The effect was strongest when the F atom lay directly opposite the base, resulting in a halogen > chalcogen > pnicogen > tetrel order of bond strength. Replacing third-row atoms by their second-row counterparts weakened the bonds, but not uniformly. Tetrel bonds were weakest for the fully hydrogenated acids and surpassed pnicogen bonds when F had been added to the acid. Full article
(This article belongs to the Special Issue Tetrel Bonds)
Figures

Graphical abstract

Open AccessArticle Comparison between Tetrel Bonded Complexes Stabilized by σ and π Hole Interactions
Molecules 2018, 23(6), 1416; https://doi.org/10.3390/molecules23061416
Received: 30 May 2018 / Revised: 8 June 2018 / Accepted: 9 June 2018 / Published: 11 June 2018
Cited by 1 | PDF Full-text (1520 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The σ-hole tetrel bonds formed by a tetravalent molecule are compared with those involving a π-hole above the tetrel atom in a trivalent bonding situation. The former are modeled by TH4, TH3F, and TH2F2 (T =
[...] Read more.
The σ-hole tetrel bonds formed by a tetravalent molecule are compared with those involving a π-hole above the tetrel atom in a trivalent bonding situation. The former are modeled by TH4, TH3F, and TH2F2 (T = Si, Ge, Sn) and the latter by TH2=CH2, THF=CH2, and TF2=CH2, all paired with NH3 as Lewis base. The latter π-bonded complexes are considerably more strongly bound, despite the near equivalence of the σ and π-hole intensities. The larger binding energies of the π-dimers are attributed to greater electrostatic attraction and orbital interaction. Each progressive replacement of H by F increases the strength of the tetrel bond, whether σ or π. The magnitudes of the maxima of the molecular electrostatic potential in the two types of systems are not good indicators of either the interaction energy or even the full Coulombic energy. The geometry of the Lewis acid is significantly distorted by the formation of the dimer, more so in the case of the σ-bonded complexes, and this deformation intensifies the σ and π holes. Full article
(This article belongs to the Special Issue Tetrel Bonds)
Figures

Graphical abstract

Open AccessFeature PaperArticle Tetrel Bonds with π-Electrons Acting as Lewis Bases—Theoretical Results and Experimental Evidences
Molecules 2018, 23(5), 1183; https://doi.org/10.3390/molecules23051183
Received: 30 April 2018 / Revised: 11 May 2018 / Accepted: 11 May 2018 / Published: 15 May 2018
Cited by 2 | PDF Full-text (2317 KB) | HTML Full-text | XML Full-text
Abstract
MP2/aug-cc-pVTZ calculations were carried out for the ZFH3-B complexes (Z = C, Si, Ge, Sn and Pb; B = C2H2, C2H4, C6H6 and C5H5-; relativistic
[...] Read more.
MP2/aug-cc-pVTZ calculations were carried out for the ZFH3-B complexes (Z = C, Si, Ge, Sn and Pb; B = C2H2, C2H4, C6H6 and C5H5-; relativistic effects were taken into account for Ge, Sn and Pb elements). These calculations are supported by other approaches; the decomposition of the energy of interaction, Quantum Theory of Atoms in Molecules (QTAIM) and Natural Bond Orbital (NBO) method. The results show that tetrel bonds with π-electrons as Lewis bases are classified as Z···C links between single centers (C is an atom of the π-electron system) or as Z···π interactions where F‒Z bond is directed to the mid-point (or nearly so) of the CC bond of the Lewis base. The analogous systems with Z···C/π interactions were found in the Cambridge Structural Database (CSD). It was found that the strength of interaction increases with the increase of the atomic number of the tetrel element and that for heavier tetrel elements the ZFH3 tetrahedral structure is more deformed towards the structure with the planar ZH3 fragment. The results of calculations show that the tetrel bond is sometimes accompanied by the Z-H···C hydrogen bond or even sometimes the ZFH3-B complexes are linked only by the hydrogen bond interaction. Full article
(This article belongs to the Special Issue Tetrel Bonds)
Figures

Figure 1

Open AccessFeature PaperArticle Tetrel Bonding as a Vehicle for Strong and Selective Anion Binding
Molecules 2018, 23(5), 1147; https://doi.org/10.3390/molecules23051147
Received: 24 April 2018 / Revised: 7 May 2018 / Accepted: 9 May 2018 / Published: 11 May 2018
Cited by 1 | PDF Full-text (1562 KB) | HTML Full-text | XML Full-text
Abstract
Tetrel atoms T (T = Si, Ge, Sn, and Pb) can engage in very strong noncovalent interactions with nucleophiles, which are commonly referred to as tetrel bonds. The ability of such bonds to bind various anions is assessed with a goal of designing
[...] Read more.
Tetrel atoms T (T = Si, Ge, Sn, and Pb) can engage in very strong noncovalent interactions with nucleophiles, which are commonly referred to as tetrel bonds. The ability of such bonds to bind various anions is assessed with a goal of designing an optimal receptor. The Sn atom seems to form the strongest bonds within the tetrel family. It is most effective in the context of a -SnF3 group and a further enhancement is observed when a positive charge is placed on the receptor. Connection of the -SnF3 group to either an imidazolium or triazolium provides a strong halide receptor, which can be improved if its point of attachment is changed from the C to an N atom of either ring. Aromaticity of the ring offers no advantage nor is a cyclic system superior to a simple alkyl amine of any chain length. Placing a pair of -SnF3 groups on a single molecule to form a bipodal dicationic receptor with two tetrel bonds enhances the binding, but falls short of a simple doubling. These two tetrel groups can be placed on opposite ends of an alkyl diamine chain of any length although SnF3+NH2(CH2)nNH2SnF3+ with n between 2 and 4 seems to offer the strongest halide binding. Of the various anions tested, OH binds most strongly: OH > F > Cl > Br > I. The binding energy of the larger NO3 and HCO3 anions is more dependent upon the charge of the receptor. This pattern translates into very strong selectivity of binding one anion over another. The tetrel-bonding receptors bind far more strongly to each anion than an equivalent number of K+ counterions, which leads to equilibrium ratios in favor of the former of many orders of magnitude. Full article
(This article belongs to the Special Issue Tetrel Bonds)
Figures

Graphical abstract

Open AccessArticle Complexes of CO2 with the Azoles: Tetrel Bonds, Hydrogen Bonds and Other Secondary Interactions
Molecules 2018, 23(4), 906; https://doi.org/10.3390/molecules23040906
Received: 31 March 2018 / Revised: 9 April 2018 / Accepted: 11 April 2018 / Published: 14 April 2018
Cited by 1 | PDF Full-text (15105 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Ab initio MP2/aug’-cc-pVTZ calculations have been performed to investigate the complexes of CO2 with the azoles pyrrole, pyrazole, imidazole, 1,2,3- and 1,2,4-triazole, tetrazole and pentazole. Three types of complexes have been found on the CO2:azole potential surfaces. These include ten
[...] Read more.
Ab initio MP2/aug’-cc-pVTZ calculations have been performed to investigate the complexes of CO2 with the azoles pyrrole, pyrazole, imidazole, 1,2,3- and 1,2,4-triazole, tetrazole and pentazole. Three types of complexes have been found on the CO2:azole potential surfaces. These include ten complexes stabilized by tetrel bonds that have the azole molecule in the symmetry plane of the complex; seven tetrel-bonded complexes in which the CO2 molecule is perpendicular to the symmetry plane; and four hydrogen-bonded complexes. Eight of the planar complexes are stabilized by Nx···C tetrel bonds and by a secondary interaction involving an adjacent Ny-H bond and an O atom of CO2. The seven perpendicular CO2:azole complexes form between CO2 and two adjacent N atoms of the ring, both of which are electron-pair donors. In three of the four hydrogen-bonded complexes, the proton-donor Nz-H bond of the ring is bonded to two C-H bonds, thereby precluding the planar and perpendicular complexes. The fourth hydrogen-bonded complex forms with the strongest acid pentazole. Binding energies, charge-transfer energies and changes in CO2 stretching and bending frequencies upon complex formation provide consistent descriptions of these complexes. Coupling constants across tetrel bonds are negligibly small, but 2hJ(Ny-C) across Nz-H···C hydrogen bonds are larger and increase as the number of N atoms in the ring increases. Full article
(This article belongs to the Special Issue Tetrel Bonds)
Figures

Graphical abstract

Planned Papers

The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.

Author: Mehdi D. Esrafili
Affiliation: Department of Chemistry University of Maragheh Maragheh, Iran
Tentative title: Very strong tetrel bonds: Theoretical aspects and experimental evidences

Author: Sławomir J. Grabowski
Affiliation: Faculty of Chemistry, University of the Basque Country and Donostia
International Physics Center (DIPC), P.K. 1072 20080 Donostia (Spain)
IKERBASQUE, Basque Foundation for Science 48011 Bilbao (Spain)
Title: Tetrel bonds with π-electron systems acting as Lewis bases – theoretical results and their experimental analogs in crystal structures
Abstract: MP2/aug-cc-pVTZ and MP2/aug-cc-pVQZ calculations were carried out for the FZH3…B complexes (Z = C, Si, Ge, Sn and Pb; B = C2H2, C2H4, C6H6 and C5H5-; relativistic effects taken into account for Ge, Sn and Pb elements ). These calculations are supported by other theoretical approaches; decomposition of the energy of interaction scheme, Quantum Theory of Atoms in Molecules (QTAIM) and Natural Bond Orbital (NBO) method. The results show that the tetrel bonds with π-electrons as the Lewis bases are classified as links between single centers, i.e. Z…C (C is an atom of the π-electron system) but not as the Z…π interactions where F-Z bond is directed to the mid-point (or nearly so) of any CC bond of the Lewis base. The analogues systems with Z…C interactions were found in the Cambridge Structural Database (CSD). It was found that the strength of interaction increases with the increase of the atomic number of the tetrel element; besides for heavier tetrel elements the tetrahedral structure of FZH3 is more deformed towards the structure with the planar ZH3 fragment.

Author: Qingzhong Li
Affiliation: The Laboratory of Theoretical and Computational Chemistry, Science and Engineering College of Chemistry and Biology, Yantai University, Yantai 264005, People's Republic of China.
Tentative title: Comparison of σ-hole and π-hole tetrel bonds of borazine with TH3F and F2TO
Tentative abstract: In this paper, we are interested in the tetrel bonding interactions between borazine and TH3F/F2TO (T = C and Si). Borazine can provide three base centers to bind with the σ-hole in TH3F and the π-hole in F2TO, including the ring center, the N atom, and the B-H bond. Do these three base centers of borazine form a stable complex with TH3F and F2TO? Which can forms the strongest tetrel bond with TH3F and F2TO? Does the relative strength of the σ-hole and π-hole interactions have dependence on the nature of a base? The geometric, energetic, and electronic properties of the minima complexes have been characterized and discussed. The origin of σ-hole and π-hole interactions has been unveiled by means of energy decomposition.

Author: Wiktor Zierkiewicz
Affiliation: Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
Tentative title: Open and closed-shell complexes of Rgn (where Rg= Cu, Ag, Au and n= 2 - 6 ) with ammonia and hydrogen cyanide stabilized by regium bond

Author: Antonio Frontera Beccaria
Affiliation: Universidad de las Islas Baleares
Tentative title: Tetrel bonding interactions in perhalopentasilolanes and perhalohexasilinanes: a combined ab initio and CSD study.
Abstract: In this manuscript, we combined a search in the Cambridge Structural Database (CSD) and ab initio calculations (RI-MP2/def2-TZVPD level of theory) to analyze the ability of perhalopentasilolanes and perhalohexasilinanes to establish tetrel bonding interactions. A preliminary CSD inspection revealed that perhalopentasilolanes and perhalohexasilinanes moieties have strong ability to establish ten and twelve tetrel bonding interactions simultaneously. In order to analyze these two relevant structural motifs, we have used a series of perhalopentasilolanes and perhalohexasilinanes derivatives and anions as electron donors. Besides, we have carried out “atoms in molecules” (AIM) and natural bonding orbital (NBO) analyses to further characterize the tetrel bonding interactions described herein.

Author: Sharon Priya Gnanasekar and Elangannan Arunan
Affiliation: Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
Tentative title: Carbon Bond – Tetrel Bond: Computational Studies on TH5+ (T = C/Si/Ge)
Tentative abstract: Pentacoordinate carbon has long been sought after and the elusive prototype is CH5+. Current understanding of its structure indicates that it could be loosely characterized as CH3+•••H2 complex. However, previous Atoms in Molecule theoretical analysis showed three short and two long C-H bonds, and no H-H bond and naturally no ‘carbon bond’ between C in CH3+ and H2. Our current work on SiH5+ and GeH5+ reveal that they look more like TH3+•••H2 complex, revealing tetrel bonds between the T atom in TH3+ and the bond critical point in H2. Our article will focus on these and similar systems and compare the tetrel bonds formed by C/Si/Ge.

Author: Elfi Kraka
Affiliation: Professor and Chair
Computational and Theoretical Chemistry Group CATCO (http://smu.edu/catco/)
Department of Chemistry Dedman College SMU, Southern Methodist University
3215 Daniel Ave
Tentative title: Tetrel bond strength - A quantitative assessment based on vibrational spectroscopy
Tentative abstract: The tetrel bond strength of a set of complexes involving sp3 and sp2 hybridized C and Si atoms will be determined quantitatively with
the help of the local stretching force constant associated with the tetrel bond, computed at the CCSD level of theory. The nature of tetrel bonding interactions and the underlying bonding mechanism will be investigated on the basis of the analysis of electron and energy densities, molecular electrostatic potentials, molecular orbitals and natural bond orbitals. Similarities and differences between tetrel bonding and other weak interactions such as pnicogen, chalcogen and halogen bonding in neutral and anionic complexes will be discussed in detail. The importance of tetrel bonding for crystal engineering and biological systems will be explored.

Back to Top