scholarly journals Structural, Hirshfeld and DFT studies of conjugated D–π–A carbazole chalcone crystal

2020 ◽  
Vol 76 (3) ◽  
pp. 387-391
Author(s):  
Muhamad Fikri Zaini ◽  
Ibrahim Abdul Razak ◽  
Wan Mohd Khairul ◽  
Suhana Arshad
Keyword(s):  
Density Functional ◽  
Molecular Electrostatic Potential ◽  
Crystal Packing ◽  
Condensation Reaction ◽  
Hirshfeld Surface ◽  
Basis Set ◽  
Dft Studies ◽  
Functional Theory ◽  
Percentage Contribution ◽  
Quantum Chemistry Calculations

A new conjugated carbazole chalcone compound, (E)-3-[4-(9,9a-dihydro-8aH-carbazol-9-yl)phenyl]-1-(4-nitrophenyl)prop-2-en-1-one (CPNC), C27H18N2O3, was synthesized using a Claisen–Schmidt condensation reaction. CPNC crystallizes in the monoclinic non-centrosymmetric space group Cc and adopts an s-cis conformation with respect to the ethylenic double bonds (C=O and C=C). The crystal packing features C—H...O and C—H...π interactions whose percentage contribution was quantified by Hirshfeld surface analysis. Quantum chemistry calculations including geometrical optimization and molecular electrostatic potential (MEP) were analysed by density functional theory (DFT) with a B3LYP/6–311 G++(d,p) basis set.

Evaluation of N—H...S and N—H...π interactions inO,O′-diethylN-(2,4,6-trimethylphenyl)thiophosphate: a combination of X-ray crystallographic and theoretical studies

2018 ◽  
Vol 74 (7) ◽  
pp. 847-855 ◽  
Author(s):  
Elham Torabi Farkhani ◽  
Mehrdad Pourayoubi ◽  
Mohammad Izadyar ◽  
Pavel V. Andreev ◽  
Ekaterina S. Shchegravina
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Density Functional ◽  
Natural Bond Orbital ◽  
Crystal Packing ◽  
Hirshfeld Surface ◽  
Basis Set ◽  
Theoretical Studies ◽  
Functional Theory ◽  
X Ray

In the crystal structure ofO,O′-diethylN-(2,4,6-trimethylphenyl)thiophosphate, C13H22NO2PS, two symmetrically independent thiophosphoramide molecules are linked through N—H...S and N—H...π hydrogen bonds to form a noncentrosymmetric dimer, withZ′ = 2. The strengths of the hydrogen bonds were evaluated using density functional theory (DFT) at the M06-2X level within the 6-311++G(d,p) basis set, and by considering the quantum theory of atoms in molecules (QTAIM). It was found that the N—H...S hydrogen bond is slightly stronger than the N—H...π hydrogen bond. This is reflected in differences between the calculated N—H stretching frequencies of the isolated molecules and the frequencies of the same N—H units involved in the different hydrogen bonds of the hydrogen-bonded dimer. For these hydrogen bonds, the corresponding charge transfers,i.e.lp (or π)→σ*, were studied, according to the second-order perturbation theory in natural bond orbital (NBO) methodology. Hirshfeld surface analysis was applied for a detailed investigation of all the contacts participating in the crystal packing.

scholarly journals Crystal structure, Hirshfeld surface analysis and DFT studies of (E)-1-(4-bromophenyl)-3-(3-fluorophenyl)prop-2-en-1-one

2019 ◽  
Vol 75 (1) ◽  
pp. 58-63 ◽  
Author(s):  
Muhamad Fikri Zaini ◽  
Ibrahim Abdul Razak ◽  
Mohamad Zahid Anis ◽  
Suhana Arshad
Keyword(s):  
Surface Analysis ◽  
Density Functional ◽  
Significant Contribution ◽  
Energy Gap ◽  
Crystal Packing ◽  
Hirshfeld Surface ◽  
Basis Set ◽  
Hirshfeld Surface Analysis ◽  
Functional Theory ◽  
Homo Lumo

The asymmetric unit of the title halogenated chalcone derivative, C15H10BrFO, contains two independent molecules, both adopting an s-cis configuration with respect to the C=O and C=C bonds. In the crystal, centrosymmetrically related molecules are linked into dimers via intermolecular hydrogen bonds, forming rings with R 1 2(6), R 2 2(10) and R 2 2(14) graph-set motifs. The dimers are further connected by C—H...O interactions into chains parallel to [001]. A Hirshfeld surface analysis suggests that the most significant contribution to the crystal packing is by H...H contacts (26.3%). Calculations performed on the optimized structure obtained using density functional theory (DFT) at B3LYP with the 6–311 G++(d,p) basis set reveal that the HOMO–LUMO energy gap is 4.12 eV, indicating the suitability of this crystal for optoelectronic and biological applications. The nucleophilic and electrophilic binding site regions are elucidated using the molecular electrostatic potential (MEP).

scholarly journals Crystal structure, Hirshfeld surface analysis and interaction energy and DFT studies of 2-(2,3-dihydro-1H-perimidin-2-yl)-6-methoxyphenol

2020 ◽  
Vol 76 (5) ◽  
pp. 605-610
Author(s):  
Ballo Daouda ◽  
Nanou Tiéba Tuo ◽  
Tuncer Hökelek ◽  
Kangah Niameke Jean-Baptiste ◽  
Kodjo Charles Guillaume ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Surface Analysis ◽  
Density Functional ◽  
Energy Gap ◽  
Crystal Packing ◽  
Hirshfeld Surface ◽  
Van Der Waals Interactions ◽  
Hirshfeld Surface Analysis ◽  
Functional Theory ◽  
Compound C

The title compound, C18H16N2O2, consists of perimidine and methoxyphenol units, where the tricyclic perimidine unit contains a naphthalene ring system and a non-planar C4N2 ring adopting an envelope conformation with the NCN group hinged by 47.44 (7)° with respect to the best plane of the other five atoms. In the crystal, O—HPhnl...NPrmdn and N—HPrmdn...OPhnl (Phnl = phenol and Prmdn = perimidine) hydrogen bonds link the molecules into infinite chains along the b-axis direction. Weak C—H...π interactions may further stabilize the crystal structure. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H...H (49.0%), H...C/C...H (35.8%) and H...O/O...H (12.0%) interactions. Hydrogen bonding and van der Waals interactions are the dominant interactions in the crystal packing. Computational chemistry indicates that in the crystal, the O—HPhnl...NPrmdn and N—HPrmdn...OPhnl hydrogen-bond energies are 58.4 and 38.0 kJ mol−1, respectively. Density functional theory (DFT) optimized structures at the B3LYP/ 6–311 G(d,p) level are compared with the experimentally determined molecular structure in the solid state. The HOMO–LUMO behaviour was elucidated to determine the energy gap.

scholarly journals Crystal structure, Hirshfeld surface analysis and DFT study of N-(2-amino-5-methylphenyl)-2-(5-methyl-1H-pyrazol-3-yl)acetamide

2021 ◽  
Vol 77 (6) ◽  
pp. 638-642
Author(s):  
Gamal Al Ati ◽  
Karim Chkirate ◽  
Joel T. Mague ◽  
Nadeem Abad ◽  
Redouane Achour ◽  
...  
Keyword(s):  
Surface Analysis ◽  
Density Functional ◽  
Energy Gap ◽  
Crystal Packing ◽  
Layer Structure ◽  
Hirshfeld Surface ◽  
Hirshfeld Surface Analysis ◽  
Lumo Energy ◽  
Functional Theory ◽  
Homo Lumo

The title molecule, C13H16N4O, adopts an angular conformation. In the crystal a layer structure is generated by N—H...O and N—H...N hydrogen bonds together with C—H...π(ring) interactions. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H...H (53.8%), H...C/C...H (21.7%), H...N/N...H (13.6%), and H...O/O...H (10.8%) interactions. The optimized structure calculated using density functional theory (DFT) at the B3LYP/ 6–311 G(d,p) level is compared with the experimentally determined structure in the solid state. The calculated HOMO–LUMO energy gap is 5.0452 eV.

scholarly journals Crystal structure, Hirshfeld surface analysis and interaction energy and DFT studies of 1-(1,3-benzothiazol-2-yl)-3-(2-hydroxyethyl)imidazolidin-2-one

2020 ◽  
Vol 76 (3) ◽  
pp. 370-376
Author(s):  
Mohamed Srhir ◽  
Nada Kheira Sebbar ◽  
Tuncer Hökelek ◽  
Ahmed Moussaif ◽  
Joel T. Mague ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Surface Analysis ◽  
Density Functional ◽  
Crystal Packing ◽  
Layer Structure ◽  
Hirshfeld Surface ◽  
Van Der Waals Interactions ◽  
Hirshfeld Surface Analysis ◽  
Functional Theory ◽  
Hydrogen Bond Energies

In the title molecule, C12H13N3O2S, the benzothiazine moiety is slightly non-planar, with the imidazolidine portion twisted only a few degrees out of the mean plane of the former. In the crystal, a layer structure parallel to the bc plane is formed by a combination of O—HHydethy...NThz hydrogen bonds and weak C—HImdz...OImdz and C—HBnz...OImdz (Hydethy = hydroxyethyl, Thz = thiazole, Imdz = imidazolidine and Bnz = benzene) interactions, together with C—HImdz...π(ring) and head-to-tail slipped π-stacking [centroid-to-centroid distances = 3.6507 (7) and 3.6866 (7) Å] interactions between thiazole rings. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H...H (47.0%), H...O/O...H (16.9%), H...C/C...H (8.0%) and H...S/S...H (7.6%) interactions. Hydrogen bonding and van der Waals interactions are the dominant interactions in the crystal packing. Computational chemistry indicates that in the crystal, C—H...N and C—H...O hydrogen-bond energies are 68.5 (for O—HHydethy...NThz), 60.1 (for C—HBnz...OImdz) and 41.8 kJ mol−1 (for C—HImdz...OImdz). Density functional theory (DFT) optimized structures at the B3LYP/6–311 G(d,p) level are compared with the experimentally determined molecular structure in the solid state.

scholarly journals Crystal structure, Hirshfeld surface analysis and DFT studies of 6-bromo-3-(12-bromododecyl)-2-(4-nitrophenyl)-4H-imidazo[4,5-b]pyridine

2020 ◽  
Vol 76 (5) ◽  
pp. 677-682 ◽  
Author(s):  
Zainab Jabri ◽  
Karim Jarmoni ◽  
Tuncer Hökelek ◽  
Joel T. Mague ◽  
Safia Sabir ◽  
...  
Keyword(s):  
Surface Analysis ◽  
Density Functional ◽  
Energy Gap ◽  
Crystal Packing ◽  
Hirshfeld Surface ◽  
Hirshfeld Surface Analysis ◽  
Side Chain ◽  
Functional Theory ◽  
Compound C ◽  
Homo Lumo

The title compound, C24H30Br2N4O2, consists of a 2-(4-nitrophenyl)-4H-imidazo[4,5-b]pyridine entity with a 12-bromododecyl substituent attached to the pyridine N atom. The middle eight-carbon portion of the side chain is planar to within 0.09 (1) Å and makes a dihedral angle of 21.9 (8)° with the mean plane of the imidazolopyridine moiety, giving the molecule a V-shape. In the crystal, the imidazolopyridine units are associated through slipped π–π stacking interactions together with weak C—HPyr...ONtr and C—HBrmdcyl...ONtr (Pyr = pyridine, Ntr = nitro and Brmdcyl = bromododecyl) hydrogen bonds. The 12-bromododecyl chains overlap with each other between the stacks. The terminal –CH2Br group of the side chain shows disorder over two resolved sites in a 0.902 (3):0.098 (3) ratio. Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are from H...H (48.1%), H...Br/Br...H (15.0%) and H...O/O...H (12.8%) interactions. The optimized molecular structure, using density functional theory at the B3LYP/ 6–311 G(d,p) level, is compared with the experimentally determined structure in the solid state. The HOMO–LUMO behaviour was elucidated to determine the energy gap.

scholarly journals Theoretical Evaluation on The Interaction Between Triglycerides and Methylxanthines Using Density Functional Theory B3LYP/6-31G(d,p) and Molecular Electrostatic Potential

2020 ◽  
Vol 33 (1) ◽  
pp. 171-178
Author(s):  
N.F.M. Azmi ◽  
R. Ali ◽  
A.A. Azmi ◽  
M.Z.H. Rozaini ◽  
K.H.K. Bulat ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Hydrogen Bond ◽  
Electrostatic Potential ◽  
Density Functional ◽  
Molecular Electrostatic Potential ◽  
Basis Set ◽  
Individual Species ◽  
Interaction Energies ◽  
Binding Interaction ◽  
Functional Theory

The binding, interaction and distortion energies between the main triglycerides, palmitic-oleic-stearic (POS) in cocoa butter versus palmitic-oleic-palmitic (POP) in refined, bleached and deodorized (RBD) palm oil with cocoa′s methylxanthines (caffeine, theobromine, and theophylline) during the production of chocolate were theoretically studied and reported. The quantum mechanical software package of Gaussian09 at the theoretical level of density functional theory B3LYP/6-31G(d,p) was employed for all calculations, optimization, and basis set superposition errors (BSSE). Geometry optimizations were carried out to the minimum potential energy of individual species and binary complexes formed between the triglycerides, methylxanthines and polyphenols. The interaction energies for the optimized complexes were then corrected for the BSSE using the counterpoise method of Boys and Bernardi. The results revealed that the binding energy and interaction energy between methylxanthine components in cocoa powder with triglycerides were almost of the same magnitude (13.6-14.5 and 3.4-3.7 kJ/mol, respectively), except for the binary complex of POS-caffeine (25.1 and 10.7 kJ/mol, respectively). Based on the molecular geometry results, the hydrogen bond length and angle correlated well with the interaction energies. Meanwhile, the POS-caffeine complex with two higher and almost linear bond angles showed higher binding and interaction energies as compared to the other methylxanthines. Therefore, a donor-acceptor analysis showed that the hydrogen bond strength was proven using the molecular electrostatic potential (MEP), which resulted in parallel outcomes. The research results were believed to be one of the factors that contributed to the rheological behaviour and sensory perception of cocoa products, especially chocolate.

Spectroscopic and Bioactivity Analysis of Naturally Occurring Methyl Ester of Chlorogenic Acid Using Density Functional Theory Based Quantum Chemical Computation

2019 ◽  
Vol 17 (10) ◽  
pp. 822-825 ◽  
Author(s):  
Ashok Kumar Mishra ◽  
Satya Prakash Tewari
Keyword(s):  
Density Functional Theory ◽  
Molecular Orbital ◽  
Density Functional ◽  
Basis Set ◽  
Theory Approach ◽  
Functional Theory ◽  
Naturally Occurring ◽  
Quantum Chemistry Calculations ◽  
Spectroscopic Characteristics ◽  
Title Molecule

The present study describes the spectroscopic characteristics like IR and Raman active vibrations, (1H, 13C) nuclear magnetic resonance (NMR) chemical shifts and UV-Visible spectra of the molecular geometry obtained using quantum chemistry calculations based on density functional theory approach via B3LYP hybrid functional at 6-31 + G(d, p) basis set of title bioactive natural compound. The calculated highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy gap in titled compound is –0.14327 eV which is reasonably small and may be the prime reason for its bioactivity. Theoretical IR active vibration spectra show the maximum peak at 1146 cm–1. The maximum absorption in UV-Vis spectrum has been observed to be occurred at 329 nm. The biological activity has also been examined through virtual screening using molecular docking approach. The calculated spectroscopic characteristics are well aligned with their experi- mental counterparts. The obtained docking score predicts the title molecule to be a good naturally occurring anti diabetic agent. The outcomes of our investigation would be useful for deriving the structural analog of the title molecule for developing an efficient naturopathic anti diabetic drug agent with less side effects.

scholarly journals Crystal structure, Hirshfeld surface analysis and interaction energy and DFT studies of 2-chloroethyl 2-oxo-1-(prop-2-yn-1-yl)-1,2-dihydroquinoline-4-carboxylate

2019 ◽  
Vol 75 (10) ◽  
pp. 1411-1417
Author(s):  
Sonia Hayani ◽  
Yassir Filali Baba ◽  
Tuncer Hökelek ◽  
Fouad Ouazzani Chahdi ◽  
Joel T. Mague ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Surface Analysis ◽  
Density Functional ◽  
Energy Gap ◽  
Crystal Packing ◽  
Hirshfeld Surface ◽  
Van Der Waals Interactions ◽  
Hirshfeld Surface Analysis ◽  
Functional Theory ◽  
Compound C

The title compound, C15H12ClNO3, consists of a 1,2-dihydroquinoline-4-carboxylate unit with 2-chloroethyl and propynyl substituents, where the quinoline moiety is almost planar and the propynyl substituent is nearly perpendicular to its mean plane. In the crystal, the molecules form zigzag stacks along the a-axis direction through slightly offset π-stacking interactions between inversion-related quinoline moieties which are tied together by intermolecular C—HPrpnyl...OCarbx and C—HChlethy...OCarbx (Prpnyl = propynyl, Carbx = carboxylate and Chlethy = chloroethyl) hydrogen bonds. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H...H (29.9%), H...O/O...H (21.4%), H...C/C... H (19.4%), H...Cl/Cl...H (16.3%) and C...C (8.6%) interactions. Hydrogen bonding and van der Waals interactions are the dominant interactions in the crystal packing. Computational chemistry indicates that in the crystal, the C—HPrpnyl...OCarbx and C—HChlethy...OCarbx hydrogen bond energies are 67.1 and 61.7 kJ mol−1, respectively. Density functional theory (DFT) optimized structures at the B3LYP/ 6–311 G(d,p) level are compared with the experimentally determined molecular structure in the solid state. The HOMO–LUMO behaviour was elucidated to determine the energy gap.

Experimental and theoretical approach to novel polyfunctionalized isoxazole

2021 ◽  
Vol 25 ◽  
Author(s):  
Amal Al-Azmi ◽  
Mona A. Shalaby
Keyword(s):  
Density Functional ◽  
Molecular Electrostatic Potential ◽  
Atomic Orbital ◽  
Spectroscopic Studies ◽  
Basis Set ◽  
Reaction Conditions ◽  
Functional Theory ◽  
1H And 13C Nmr ◽  
13C Nuclear Magnetic Resonance ◽  
The Density Functional Theory

: A novel, fast, and straightforward procedure for the synthesis of di- and tri-functionalized isoxazoles starting from 2-ethoxymethylenemalononitrile with different ratios of hydroxylamine in the presence of sodium acetate is described in this paper. The current method’s features include the availability of the starting materials, moderate reaction conditions, and the simplicity of the workup. The structures are characterized using different spectroscopic studies, such as infrared (IR), 1H/13C nuclear magnetic resonance (NMR), and elemental analysis, in addition to X-ray single-crystal determination. The gauge-invariant atomic orbital (GIAO) 1H and 13C NMR chemical shift values of 5-aminoisoxazole-4-carbonitrile and 3,5-diaminoisoxazole-4-carboxamide are calculated in the ground state using the density functional theory (DFT) with the 6- 311+G(d, p) basis set and are compared with the experimental data, in addition to the calculation of the molecular electrostatic potential (MEP) distribution, and the frontier molecular orbitals (FMOs) for the synthesized isoxazoles are illustrated theoretically.

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