scholarly journals Weak Interactions in Cocrystals of Isoniazid with Glycolic and Mandelic Acids

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 328
Author(s):  
Raquel Álvarez-Vidaurre ◽  
Alfonso Castiñeiras ◽  
Antonio Frontera ◽  
Isabel García-Santos ◽  
Diego M. Gil ◽  
...  
Keyword(s):  
Density Functional ◽  
Glycolic Acid ◽  
Weak Interactions ◽  
Three Dimensional ◽  
Functional Theory ◽  
Molecular Systems ◽  
X Ray Crystallography ◽  
Hydroxycarboxylic Acids ◽  
Non Covalent Interactions ◽  
Covalent Interactions

This work deals with the preparation of pyridine-3-carbohydrazide (isoniazid, inh) cocrystals with two α-hydroxycarboxylic acids. The interaction of glycolic acid (H2ga) or d,l-mandelic acid (H2ma) resulted in the formation of cocrystals or salts of composition (inh)·(H2ga) (1) and [Hinh]+[Hma]–·(H2ma) (2) when reacted with isoniazid. An N′-(propan-2-ylidene)isonicotinic hydrazide hemihydrate, (pinh)·1/2(H2O) (3), was also prepared by condensation of isoniazid with acetone in the presence of glycolic acid. These prepared compounds were well characterized by elemental analysis, and spectroscopic methods, and their three-dimensional molecular structure was determined by single crystal X-ray crystallography. Hydrogen bonds involving the carboxylic acid occur consistently with the pyridine ring N atom of the isoniazid and its derivatives. The remaining hydrogen-bonding sites on the isoniazid backbone vary based on the steric influences of the derivative group. These are contrasted in each of the molecular systems. Finally, Hirshfeld surface analysis and Density-functional theory (DFT) calculations (including NCIplot and QTAIM analyses) have been performed to further characterize and rationalize the non-covalent interactions.

Probing non-covalent interactions driving molecular assembly in organo-electronic building blocks

CrystEngComm ◽  
2019 ◽  
Vol 21 (20) ◽  
pp. 3151-3157 ◽  
Author(s):  
Sarah N. Johnson ◽  
Thomas L. Ellington ◽  
Duong T. Ngo ◽  
Jorge L. Nevarez ◽  
Nicholas Sparks ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Density Functional ◽  
Building Blocks ◽  
Molecular Assembly ◽  
Functional Theory ◽  
X Ray ◽  
X Ray Crystallography ◽  
Non Covalent Interactions ◽  
Density Functional Theory Computations ◽  
Covalent Interactions

One co-crystal structure characterized to identify and quantify various non-covalent interactions with spectroscopy, X-ray crystallography and density functional theory computations.

Organometallic pyrene-containing porphyrins: Synthesis, characterization, and non-covalent interactions with C60 fullerenes

2016 ◽  
Vol 20 (08n11) ◽  
pp. 1098-1113 ◽  
Author(s):  
Yang Li ◽  
Hannah M. Rhoda ◽  
Anthony M. Wertish ◽  
Victor N. Nemykin
Keyword(s):  
Excited States ◽  
Electronic Structures ◽  
Density Functional ◽  
Functional Theory ◽  
X Ray ◽  
X Ray Crystallography ◽  
H Nmr ◽  
Non Covalent Interactions ◽  
Covalent Interactions ◽  
C60 Fullerenes

A reaction between 5,10,15,20-tetra(4-hydroxyphenyl)porphyrin and 1-bromopyrene resulted in the formation of 5,10,15,20-tetra[4-(4-(pyrenyl-1)butoxy)phenyl]porphyrin (1), while cross-condensation between 4-(4-(pyrenyl-1)butoxy)benzaldehyde, ferrocenecaboxaldehyde, and pyrrole resulted in the formation of 5-ferrocenyl-10,15,20-tri[4-(4-(pyrenyl-1)butoxy)phenyl]porphyrin (2), 5,10-diferrocenyl-15,20-di[4-(4-(pyrenyl-1)butoxy)phenyl]porphyrin (3), and 5,15-diferrocenyl-10,20-di[4-(4-(pyrenyl-1)butoxy)phenyl]porphyrin (4). All pyrene-containing porphyrins were characterized by 1H NMR, UV-vis, MCD, and high-resolution ESI methods, while their electronic structures and the nature of the excited states were elucidated using density functional theory (DFT) and time-dependent DFT (TDDFT) calculations. The molecular structure of 1 and its fluorescence quenching upon the addition of C[Formula: see text] fullerene was also investigated using X-ray crystallography and steady-state fluorescence approaches.

scholarly journals 1,3,5-Triaza-7-Phosphaadamantane (PTA) as a 31P NMR Probe for Organometallic Transition Metal Complexes in Solution

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1390 ◽  
Author(s):  
Ilya G. Shenderovich
Keyword(s):  
Chemical Shift ◽  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Density Functional ◽  
Molecular Structures ◽  
Basis Sets ◽  
Functional Theory ◽  
Non Covalent Interactions ◽  
Covalent Interactions

Due to the rigid structure of 1,3,5-triaza-7-phosphaadamantane (PTA), its 31P chemical shift solely depends on non-covalent interactions in which the molecule is involved. The maximum range of change caused by the most common of these, hydrogen bonding, is only 6 ppm, because the active site is one of the PTA nitrogen atoms. In contrast, when the PTA phosphorus atom is coordinated to a metal, the range of change exceeds 100 ppm. This feature can be used to support or reject specific structural models of organometallic transition metal complexes in solution by comparing the experimental and Density Functional Theory (DFT) calculated values of this 31P chemical shift. This approach has been tested on a variety of the metals of groups 8–12 and molecular structures. General recommendations for appropriate basis sets are reported.

scholarly journals Atoms in Highly Symmetric Environments: H in Rhodium and Cobalt Cages, H in an Octahedral Hole in MgO, and Metal Atoms Ca-Zn in C20 Fullerenes

Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1281
Author(s):  
Zikri Altun ◽  
Erdi Ata Bleda ◽  
Carl Trindle
Keyword(s):  
Density Functional Theory ◽  
Quantum Theory ◽  
Coordination Number ◽  
Electronic Structures ◽  
Density Functional ◽  
Functional Theory ◽  
Metal Atoms ◽  
Tetragonal Pyramidal ◽  
Non Covalent Interactions ◽  
Covalent Interactions

An atom trapped in a crystal vacancy, a metal cage, or a fullerene might have many immediate neighbors. Then, the familiar concept of valency or even coordination number seems inadequate to describe the environment of that atom. This difficulty in terminology is illustrated here by four systems: H atoms in tetragonal-pyramidal rhodium cages, H atom in an octahedral cobalt cage, H atom in a MgO octahedral hole, and metal atoms in C20 fullerenes. Density functional theory defines structure and energetics for the systems. Interactions of the atom with its container are characterized by the quantum theory of atoms in molecules (QTAIM) and the theory of non-covalent interactions (NCI). We establish that H atoms in H2Rh13(CO)243− trianion cannot be considered pentavalent, H atom in HCo6(CO)151− anion cannot be considered hexavalent, and H atom in MgO cannot be considered hexavalent. Instead, one should consider the H atom to be set in an environmental field defined by its 5, 6, and 6 neighbors; with interactions described by QTAIM. This point is further illustrated by the electronic structures and QTAIM parameters of M@C20, M=Ca to Zn. The analysis describes the systematic deformation and restoration of the symmetric fullerene in that series.

scholarly journals Mechanochemical Synthesis of a Mercury(II) Metal-Organic Framework Reveals a Two-Dimensional Polymorph Stabilized by Weak Interactions

2019 ◽  
Author(s):  
Isaiah R. Speight ◽  
Igor Huskić ◽  
Mihails Arhangelskis ◽  
Hatem M. Titi ◽  
Robin Stein ◽  
...  
Keyword(s):  
Density Functional ◽  
Weak Interactions ◽  
Metal Organic Framework ◽  
Three Dimensional ◽  
Density Functional Theory Calculations ◽  
Dimensional Structure ◽  
Reaction Monitoring ◽  
Two Dimensional ◽  
Functional Theory ◽  
Metal Organic

Solid-state mechanochemistry revealed a novel polymorph of the mercury(II) imidazolate framework, based on square-grid (sql) topology layers. Reaction monitoring and periodic density functional theory calculations show that the sql-structure is of higher stability than the previously reported three-dimensional structure, with the unexpected stabilization of a lower dimensionality structure explained by contributions of weak interactions, which include short C-H···Hg contacts.

scholarly journals Armchair Boron Nitride nanotubes—heterocyclic molecules interactions: A computational description

2015 ◽  
Vol 13 (1) ◽  
Author(s):  
Ernesto Chigo Anota ◽  
Gregorio Hernández Cocoletzi ◽  
Andres Manuel Garay Tapia
Keyword(s):  
Density Functional Theory ◽  
Boron Nitride ◽  
Ab Initio Calculations ◽  
Ab Initio ◽  
Density Functional ◽  
Boron Nitride Nanotubes ◽  
Functional Theory ◽  
Heterocyclic Molecules ◽  
Non Covalent Interactions ◽  
Covalent Interactions

AbstractAb-initio calculations using density functional theory (DFT) are used to investigate the non-covalent interactions between single wall armchair boron nitride nanotubes (BNNTs) with open ends and several heterocyclic molecules: thiophene (T; C

scholarly journals Mechanochemical Synthesis of a Mercury(II) Metal-Organic Framework Reveals a Two-Dimensional Polymorph Stabilized by Weak Interactions

2019 ◽  
Author(s):  
Isaiah R. Speight ◽  
Igor Huskić ◽  
Mihails Arhangelskis ◽  
Hatem M. Titi ◽  
Robin Stein ◽  
...  
Keyword(s):  
Density Functional ◽  
Weak Interactions ◽  
Metal Organic Framework ◽  
Three Dimensional ◽  
Density Functional Theory Calculations ◽  
Dimensional Structure ◽  
Reaction Monitoring ◽  
Two Dimensional ◽  
Functional Theory ◽  
Metal Organic

Solid-state mechanochemistry revealed a novel polymorph of the mercury(II) imidazolate framework, based on square-grid (sql) topology layers. Reaction monitoring and periodic density functional theory calculations show that the sql-structure is of higher stability than the previously reported three-dimensional structure, with the unexpected stabilization of a lower dimensionality structure explained by contributions of weak interactions, which include short C-H···Hg contacts.

scholarly journals Strength and Nature of Host-Guest Interactions in Metal-Organic Frameworks from a Quantum-Chemical Perspective

2021 ◽  
Author(s):  
Michelle Enst ◽  
Ganna Gryn'ova
Keyword(s):  
Density Functional Theory ◽  
Quantum Chemical ◽  
Density Functional ◽  
Metal Organic Frameworks ◽  
Energy Decomposition ◽  
Functional Theory ◽  
Metal Organic ◽  
Non Covalent Interactions ◽  
Decomposition Schemes ◽  
Covalent Interactions

<div> <div> <div> <p>Metal-organic frameworks offer a convenient means for capturing, transporting, and releasing small molecules. Rational design of such systems requires an in-depth understanding of the underlying non-covalent interactions, and the ability to easily and rapidly pre-screen candidate architectures in silico. In this work, we devised a recipe for computing the strength and analysing the nature of the host-guest interactions in MOFs. Using experimentally characterised complexes of calcium-adipate framework with 4,4’-bipyridine and 1,2-bis(4-pyridyl)ethane guests as test systems, we have assessed a range of density functional theory methods, energy decomposition schemes, and non-covalent interactions indicators across realistic periodic and finite supramolecular cluster scales. We find that appropriately constructed clusters readily reproduce the key interactions occurring in periodic models at a fraction of the computational cost and with an added benefit of diverse density partitioning schemes. Host-guest interaction energies can be reliably computed with dispersion- corrected density functional theory methods; however, decoding their precise nature demands insights from energy decomposition schemes and quantum-chemical tools beyond local bonding indices (e.g., the quantum theory of atoms in molecules), such as the non-covalent interactions index and the density overlap regions indicator. </p> </div> </div> </div>

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