scholarly journals Thermomechanical effect in molecular crystals: the role of halogen-bonding interactions

IUCrJ ◽  
2017 ◽  
Vol 4 (6) ◽  
pp. 812-823 ◽  
Author(s):  
Sudhir Mittapalli ◽  
D. Sravanakumar Perumalla ◽  
Jagadeesh Babu Nanubolu ◽  
Ashwini Nangia
Keyword(s):  
Bond Strength ◽  
Thermal Effects ◽  
Halogen Bond ◽  
Molecular Crystals ◽  
Thermal Response ◽  
Halogen Bonding ◽  
Cell Parameters ◽  
Design And Synthesis ◽  
Compound C ◽  
Thermomechanical Effect

The design and synthesis of mechanically responsive materials is interesting because they are potential candidates to convert thermal energy into mechanical work. Reported in this paper are thermosalient effects in a series of halogen derivatives of salinazids. The chloro derivative, with higher electronegativity and a weaker inter-halogen bond strength (Cl...Cl) exhibits an excellent thermal response, whereas the response is weaker in the iodo derivative with stronger I...I halogen bonding. 3,5-Dichlorosalinazid (Compound-A) exists in three polymorphic forms, two room-temperature polymorphs (Forms I and II) and one high-temperature modification (Form III). The transformation of Form I to Form III upon heating at 328–333 K is a reversible thermosalient transition, whereas the transformation of Form II to Form III is irreversible and non-thermosalient. 3,5-Dibromo- (Compound-B) and 3-bromo-5-chloro- (Compound-C) salinazid are both dimorphic: the Form I to Form II transition in Compound-B is irreversible, whereas Compound-C shows a reversible thermosalient effect (362–365 K). In the case of 3,5-diiodosalinazid (Compound-D) and 3,5-difluorosalinazid (Compound-E), no phase transitions or thermal effects were observed. The thermosalient behaviour of these halosalinazid molecular crystals is understood from the anisotropy in the cell parameters (an increase in theaaxis and a decrease in thebandcaxes upon heating) and the sudden release of accumulated strain during the phase transition. The di-halogen salinazid derivatives (chlorine to iodine) show a decrease in thermal effects with an increase in halogen-bond strength. Interestingly, Compound-B shows solid-state photochromism in its polymorphs along with the thermosalient effect, wherein Form I is cyan and Form II is light orange.

scholarly journals In Situ Assessment of Intrinsic Strength of X-I⋯OA-Type Halogen Bonds in Molecular Crystals with Periodic Local Vibrational Mode Theory

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1589 ◽  
Author(s):  
Yunwen Tao ◽  
Yue Qiu ◽  
Wenli Zou ◽  
Sadisha Nanayakkara ◽  
Seth Yannacone ◽  
...  
Keyword(s):  
Bond Strength ◽  
Vibrational Mode ◽  
Halogen Bond ◽  
Molecular Crystals ◽  
Halogen Bonding ◽  
Halogen Bonds ◽  
Mode Theory ◽  
Local Vibrational Mode ◽  
Intrinsic Strength

Periodic local vibrational modes were calculated with the rev-vdW-DF2 density functional to quantify the intrinsic strength of the X-I⋯OA-type halogen bonding (X = I or Cl; OA: carbonyl, ether and N-oxide groups) in 32 model systems originating from 20 molecular crystals. We found that the halogen bonding between the donor dihalogen X-I and the wide collection of acceptor molecules OA features considerable variations of the local stretching force constants (0.1–0.8 mdyn/Å) for I⋯O halogen bonds, demonstrating its powerful tunability in bond strength. Strong correlations between bond length and local stretching force constant were observed in crystals for both the donor X-I bonds and I⋯O halogen bonds, extending for the first time the generalized Badger’s rule to crystals. It is demonstrated that the halogen atom X controlling the electrostatic attraction between the σ -hole on atom I and the acceptor atom O dominates the intrinsic strength of I⋯O halogen bonds. Different oxygen-containing acceptor molecules OA and even subtle changes induced by substituents can tweak the n → σ ∗ (X-I) charge transfer character, which is the second important factor determining the I⋯O bond strength. In addition, the presence of the second halogen bond with atom X of the donor X-I bond in crystals can substantially weaken the target I⋯O halogen bond. In summary, this study performing the in situ measurement of halogen bonding strength in crystalline structures demonstrates the vast potential of the periodic local vibrational mode theory for characterizing and understanding non-covalent interactions in materials.

scholarly journals Thermomechanical effect of molecular crystals and role of halogen bonding

2017 ◽  
Vol 73 (a2) ◽  
pp. C707-C707
Author(s):  
Sudhir Mittapalli ◽  
D. Sravanakumar Perumalla ◽  
Ashwini Nangia
Keyword(s):  
Molecular Crystals ◽  
Halogen Bonding ◽  
Thermomechanical Effect

scholarly journals Characterizing the interplay of Pauli repulsion, electrostatics, dispersion and charge transfer in halogen bonding with energy decomposition analysis

2018 ◽  
Vol 20 (2) ◽  
pp. 905-915 ◽  
Author(s):  
Jonathan Thirman ◽  
Elric Engelage ◽  
Stefan M. Huber ◽  
Martin Head-Gordon
Keyword(s):  
Charge Transfer ◽  
Bond Strength ◽  
Halogen Bond ◽  
Decomposition Analysis ◽  
Halogen Bonding ◽  
Energy Decomposition Analysis ◽  
Energy Decomposition ◽  
Pauli Repulsion

Variational energy decomposition analysis establishes charge-transfer as the origin of halogen bond strength differences that go against electrostatics.

scholarly journals Halogen Bonding in the Complexes of Brominated Electrophiles with Chloride Anions: From a Weak Supramolecular Interaction to a Covalent Br–Cl Bond

Crystals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1075
Author(s):  
Cody Loy ◽  
Matthias Zeller ◽  
Sergiy V. Rosokha
Keyword(s):  
Bond Strength ◽  
Halogen Bond ◽  
Covalent Bond ◽  
Halogen Bonding ◽  
Halogen Bonds ◽  
Nucleophilic Reaction ◽  
X Ray ◽  
Wide Range ◽  
Judicious Choice ◽  
Range Variation

The wide-range variation of the strength of halogen bonds (XB) not only facilitates a variety of applications of this interaction, but it also allows examining the relation (and interconversion) between supramolecular and covalent bonding. Herein, the Br…Cl halogen bonding in a series of complexes of bromosubstituted electrophiles (R-Br) with chloride anions were examined via X-ray crystallographic and computational methods. Six co-crystals showing such bonding were prepared by evaporation of solutions of R-Br and tetra-n-propylammonium chloride or using Cl− anions released in the nucleophilic reaction of 1,4-diazabicyclo[2.2.2]octane with dichloromethane in the presence of R-Br. The co-crystal comprised networks formed by 3:3 or 2:2 halogen bonding between R-Br and Cl−, with the XB lengths varying from 3.0 Å to 3.25 Å. Analysis of the crystallographic database revealed examples of associations with substantially longer and shorter Br…Cl separations. DFT computations of an extended series of R–Br…Cl− complexes confirmed that the judicious choice of brominated electrophile allows varying halogen Br…Cl bond strength and length gradually from the values common for the weak intermolecular complexes to that approaching a fully developed covalent bond. This continuity of halogen bond strength in the experimental (solid-state) and calculated associations indicates a fundamental link between the covalent and supramolecular bonding.

scholarly journals 1,3,5-Trifluoro-2,4,6-triiodobenzene–piperazine (2/1)

IUCrData ◽  
2021 ◽  
Vol 6 (10) ◽  
Author(s):  
Christelle Hajjar ◽  
Jeffrey S. Ovens ◽  
David L. Bryce
Keyword(s):  
Crystal Structure ◽  
Nitrogen Atom ◽  
Bond Angle ◽  
Halogen Bond ◽  
Covalent Bond ◽  
Halogen Bonding ◽  
The Other ◽  
Linear Interaction ◽  
Compound C ◽  
Van Der Waals Radii

The single-crystal structure of the title compound, C4H10N2·2C6F3I3, features a moderately strong halogen bond between one of the three crystallographically distinct iodine atoms and the nitrogen atom. The iodine–nitrogen distance is 2.820 (3) Å, corresponding to 80% of the sum of their van der Waals radii. The C—I...N halogen bond angle is 178.0 (1)°, consistent with the linear interaction of nitrogen via a σ-hole opposite the carbon–iodine covalent bond. The other two iodine atoms do not engage in halogen bonding. Some weak C—H...F and —H...I interactions are also observed. The complete piperazine molecule is generated by symmetry.

scholarly journals Crystal structure of (2′,3,6′-trichlorobiphenyl-2-yl)boronic acid tetrahydrofuran monosolvate

2015 ◽  
Vol 71 (12) ◽  
pp. 1471-1474 ◽  
Author(s):  
Krzysztof Durka ◽  
Tomasz Kliś ◽  
Janusz Serwatowski
Keyword(s):  
Boronic Acid ◽  
Halogen Bond ◽  
Solvent Molecule ◽  
Halogen Bonding ◽  
Acid Group ◽  
Compound C ◽  
Hydrogen Bonding Interactions ◽  
Phenyl Rings ◽  
Hydroxy Groups ◽  
Centrosymmetric Dimers

The title compound, C12H8BCl3O2·C4H8O, crystallizes as a tetrahydrofuran monosolvate. The boronic acid group adopts asyn–anticonformation and is significantly twisted along the carbon–boron bond by 69.2 (1)°, due to considerable steric hindrance from the 2′,6′-dichlorophenyl group that is locatedorthoto the boronic acid substituent. The phenyl rings of the biphenyl are almost perpendicular to one another, with a dihedral angle of 87.9 (1)° between them. In the crystal, adjacent molecules are linkedviaO—H...O interactions to form centrosymmetric dimers withR22(8) motifs, which have recently been shown to be energetically very favourable. The hydroxy groups are in ananticonformation and are also engaged in hydrogen-bonding interactions with the O atom of the tetrahydrofuran solvent molecule. Cl...Cl halogen-bonding interactions [Cl...Cl = 3.464 (1) Å] link neigbouring dimers into chains running along [010]. Further aggregation occurs due to an additional Cl...Cl halogen bond [Cl...Cl = 3.387 (1) Å].

scholarly journals Tuning the solid-state emission of liquid crystalline nitro-cyanostilbene by halogen bonding

2021 ◽  
Vol 17 ◽  
pp. 124-131
Author(s):  
Subrata Nath ◽  
Alexander Kappelt ◽  
Matthias Spengler ◽  
Bibhisan Roy ◽  
Jens Voskuhl ◽  
...  
Keyword(s):  
Liquid Crystals ◽  
Solid State ◽  
Bond Strength ◽  
Self Assembly ◽  
Liquid Crystalline ◽  
Halogen Bond ◽  
Halogen Bonding ◽  
Systematic Variation ◽  
Mesomorphic Properties

The first example of halogen-bonded fluorescent liquid crystals based on the interaction of iodofluorobenzene derivatives with nitro-cyanostilbenes is reported. The systematic variation of the fluorination degree and pattern indicates the relevance of the halogen bond strength for the induction of liquid crystalline properties. The modular self-assembly approach enables the efficient tuning of the fluorescence behaviour and mesomorphic properties of the assemblies.

scholarly journals Adenine as a Halogen Bond Acceptor: A Combined Experimental and DFT Study

Crystals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 224 ◽  
Author(s):  
Yannick Roselló ◽  
Mónica Benito ◽  
Elies Molins ◽  
Miquel Barceló-Oliver ◽  
Antonio Frontera
Keyword(s):  
Density Functional ◽  
Halogen Bond ◽  
Lone Pair ◽  
Halogen Bonding ◽  
Density Functional Theory Calculations ◽  
Functional Theory ◽  
Adenine Ring ◽  
Bonding Interaction ◽  
Donor Ability ◽  
Adenine Derivative

In this work, we report the cocrystallization of N9-ethyladenine with 1,2,4,5-tetrafluoro-3,6-diiodobenzene (TFDIB), a classical XB donor. As far as our knowledge extends, this is the first cocrystal reported to date where an adenine derivative acts as a halogen bond acceptor. In the solid state, each adenine ring forms two centrosymmetric H-bonded dimers: one using N1···HA6–N6 and the other N7···HB6–N6. Therefore, only N3 is available as a halogen bond acceptor that, indeed, establishes an N···I halogen bonding interaction with TFDIB. The H-bonded dimers and halogen bonds have been investigated via DFT (Density Functional Theory) calculations and the Bader’s Quantum Theory of Atoms In Molecules (QTAIM) method at the B3LYP/6-311+G* level of theory. The influence of H-bonding interactions on the lone pair donor ability of N3 has also been analyzed using the molecular electrostatic potential (MEP) surface calculations.

Sign in / Sign up

Export Citation Format

Share Document