Crystal structure and theoretical studies of two π-conjugated fused-ring chalcones: (E)-1-(anthracen-9-yl)-3-(9-ethyl-9H-carbazol-3-yl)prop-2-en-1-one and (E)-1-(anthracen-9-yl)-3-[4-(9H-carbazol-9-yl)phenyl]prop-2-en-1-one

The title chalcones, C31H23NO and C35H23NO, were synthesized via Claisen–Schmidt condensation reactions. Both structures were solved and refined using single-crystal X-ray diffraction data and optimized at the ground state using the density functional theory (DFT) method with the B3LYP/6-311++G(d,p) level. In the crystals, π–π interations and weak C—H...O and C—H...π interactions are observed. The effect of these intermolecular interactions in the solid state can be seen by the difference between the experimental and theoretical optimized geometrical parameters. The structures have also been characterized by UV–Vis spectroscopy. The smallest energy gaps of 2.86 and 2.96 eV enhance the nonlinear responses of such molecular systems. Hirshfeld surface analyses and 2D (two-dimensional) fingerprint plots were used to quantify the intermolecular interactions present in the crystal, indicating that these are the most important contribution to the crystal packing.

Download Full-text

Theoretical Investigation of Energetic Salts with Pentazolate Anion

Molecules ◽

10.3390/molecules25081783 ◽

2020 ◽

Vol 25 (8) ◽

pp. 1783

Author(s):

Hao-Ran Wang ◽

Chong Zhang ◽

Bing-Cheng Hu ◽

Xue-Hai Ju

Keyword(s):

Density Functional ◽

Dft Method ◽

Functional Theory ◽

Calculated Density ◽

The Density Functional Theory ◽

Energetic Salts ◽

Vertical Electron Affinity ◽

The Difference ◽

Nitrogen Contents ◽

Experimental Density

Energetic salts based on pentazolate anion (cyclo-N5−) have attracted much attention due to their high nitrogen contents. However, it is an enormous challenge to efficiently screen out an appropriate cation that can match well with cyclo-N5−. The vertical electron affinity (VEA) of the cations and vertical ionization potential (VIP) of the anions for 135 energetic salts and some cyclo-N5− salts were calculated by the density functional theory (DFT). The magnitudes of VEA and VIP, and their matchability were analyzed. The results based on the calculations at the B3LYP/6-311++G(d,p) and B3LYP/aug-cc-pVTZ levels indicate that there is an excellent compatibility between cyclo-N5− and cation when the difference between the VEA of cation and the VIP of cyclo-N5− anion is −2.8 to −1.0 eV. The densities of the salts were predicted by the DFT method. Relationship between the calculated density and the experimental density was established as ρExpt = 1.111ρcal − 0.06067 with a correlation coefficient of 0.905. This regression equation could be in turn used to calibrate the calculated density of the cyclo-N5− energetic salts accurately. This work provides a favorable way to explore the energetic salts with excellent performance based on cyclo-N5−.

Download Full-text

Synthesis of [Re2Cl4(O)2(µ-O)(3,5-lut)4] and investigation of its structure via X-ray and spectroscopic measurements and DFT calculations

Chemical Papers ◽

10.2478/s11696-013-0493-7 ◽

2014 ◽

Vol 68 (5) ◽

Cited By ~ 1

Author(s):

Sławomir Michalik ◽

Jan Małecki ◽

Natalia Młynarczyk

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Computational Study ◽

Dft Method ◽

Time Dependent ◽

Electronic Transitions ◽

X Ray Diffraction ◽

Functional Theory ◽

X Ray ◽

The Density Functional Theory

AbstractA combined experimental and computational study of the dinuclear rhenium(V) complex containing (ReO)2(µ-O) core is presented in this article. The solid-state [Re2Cl4(O)2(µ-O)(3,5-lut)4] (3,5-lut = 3,5-dimethylpyridine) complex was characterised structurally (by single crystal X-ray diffraction) and spectroscopically (by IR, NMR, UV-VIS). The electronic structure was examined using the density functional theory (DFT) method. The spin-allowed electronic transitions were calculated using the time-dependent DFT method, and the UV-VIS spectrum was discussed.

Download Full-text

Synthesis and crystal structure of methyl 3-(3-hydroxy-3-phenylprop-2-enoyl)benzoate

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989018007259 ◽

2018 ◽

Vol 74 (6) ◽

pp. 816-819

Author(s):

Irina S. Zharinova ◽

Alfiya A. Bilyalova ◽

Stanislav I. Bezzubov

Keyword(s):

Hydrogen Bond ◽

Tautomeric Form ◽

Crystal Packing ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Synthesis And Crystal Structure ◽

Compound C ◽

Vis Spectroscopy ◽

Density Map ◽

The Difference

The title compound, C17H14O4, was synthesized under mild conditions and characterized by various analytical techniques. Combined NMR and X-ray diffraction data show that the substance exists exclusively in the enol tautomeric form. An intramolecular ...O=C—C=C—OH... hydrogen bond is present in the molecular structure. The analysis of the difference density map disclosed two adjacent positions of a disordered hydrogen atom taking part in this hydrogen bond, indicating the presence of two enol tautomers in the crystal. The enol molecules are assembled through numerous C—H...π and π–π as well as weak C(aryl)—H...O interactions, thus forming a dense crystal packing. The obtained substance was also studied by UV–Vis spectroscopy and cyclic voltammetry.

Download Full-text

Synthesis and structures of three new pyridine-containing oxazoline ligands of complexes for asymmetric catalysis

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229621008202 ◽

2021 ◽

Vol 77 (9) ◽

pp. 529-536

Author(s):

Ewa Wolińska ◽

Waldemar Wysocki ◽

Danuta Branowska ◽

Zbigniew Karczmarzyk

Keyword(s):

Asymmetric Catalysis ◽

Density Functional ◽

Theoretical Calculations ◽

Dft Method ◽

X Ray Diffraction ◽

Intermolecular Hydrogen Bonds ◽

Functional Theory ◽

The Density Functional Theory ◽

Ligand Conformation ◽

Oxazoline Ligands

Three new chiral pyridine-containing oxazoline derivatives with fluorine and perfluoromethyl groups, namely, 2-({2-[(4S)-4-phenyl-4,5-dihydro-1,3-oxazol-2-yl]phenyl}amino)-5-(trifluoromethyl)pyridine, C21H16F3N3O, 2-({5-fluoro-2-[(4S)-4-isopropyl-4,5-dihydro-1,3-oxazol-2-yl]phenyl}amino)-5-(trifluoromethyl)pyridine, C18H17F4N3O, and 2-({2-[(3aR,8aS)-8,8a-dihydro-3aH-indeno[1,2-d]oxazol-2-yl]phenyl}amino)-5-(trifluoromethyl)pyridine, C22H16F3N3O, as chiral ligands in metal-catalysed asymmetric reactions, were synthesized and characterized by spectral and X-ray diffraction methods. The conformation of the molecules is influenced by strong N—H...N hydrogen bonding and weak C—H...X (X = O and N) interactions. There are no intermolecular hydrogen bonds in the crystal structures of the analysed compounds. Hirshfeld surface analysis showed that the H...H contacts constitute a high percentage of the intermolecular interactions. The conformational analysis was performed by theoretical calculations using the density functional theory (DFT) method. The mechanism of complex formation in terms of the electron-withdrawing effect of the substituents on the oxazoline ring and the ligand conformation is discussed.

Download Full-text

Molecular structure, DFT studies and UV–Vis absorption of two new linear fused ring chalcones: (E)-1-(anthracen-9-yl)-3-(2-methoxyphenyl)prop-2-en-1-one and (E)-1-(anthracen-9-yl)-3-(3-fluoro-4-methoxyphenyl)prop-2-en-1-one

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s205698901800974x ◽

2018 ◽

Vol 74 (8) ◽

pp. 1087-1092 ◽

Cited By ~ 2

Author(s):

Dian Alwani Zainuri ◽

Ibrahim Abdul Razak ◽

Suhana Arshad

Keyword(s):

Molecular Structure ◽

Density Functional ◽

Geometrical Parameters ◽

Functional Theory ◽

Molecular Systems ◽

Hydrogen Bonding Interactions ◽

Energy Gaps ◽

Vis Spectroscopy ◽

Fused Ring ◽

Homo Lumo

The title compounds, C24H18O2 and C24H17FO2, were synthesized using the Claisen–Schmidt condensation method and characterized by UV–Vis spectroscopy. Weak intermolecular C—H...O, C—H...π and π–π hydrogen-bonding interactions help to stabilize the crystal structures of both compounds. The geometrical parameters obtained from the molecular structure were optimized using density functional theory (DFT) calculations at the B3LYP/6–311++G(d,p) level, showing a good correlation with the experimental results. The small HOMO–LUMO energy gaps of 3.11 and 3.07 eV enhances the non-linear responses of these molecular systems.

Download Full-text

Synthesis, Structure, and Photophysical Properties of Yellow-Green and Blue Photoluminescent Dinuclear and Octanuclear Copper(I) Iodide Complexes with a Disilanylene-Bridged Bispyridine Ligand

Molecules ◽

10.3390/molecules26226852 ◽

2021 ◽

Vol 26 (22) ◽

pp. 6852

Author(s):

Toyotaka Nakae ◽

Hiroto Miyabe ◽

Masaki Nishio ◽

Teppei Yamada ◽

Yoshinori Yamanoi

Keyword(s):

Density Functional ◽

Crystal Packing ◽

Photophysical Properties ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

X Ray ◽

Luminescence Efficiency ◽

Π Stacking ◽

The Density Functional Theory ◽

The Difference

The synthesis, structural, and photophysical investigations of CuI complexes with a disilanylene-bridged bispyridine ligand 1 are herein presented. Dinuclear (2) and ladder-like (3) octanuclear copper(I) complexes were straightforwardly prepared by exactly controlling the ratio of CuI/ligand 1. Single-crystal X-ray analysis confirmed that dinuclear complex 2 had no apparent π…π stacking whereas octanuclear complex 3 had π…π stacking in the crystal packing. In the solid state, the complexes display yellow-green (λem = 519 nm, Φ = 0.60, τ = 11 µs, 2) and blue (λem = 478 nm, Φ = 0.04, τ = 2.6 µs, 3) phosphorescence, respectively. The density functional theory calculations validate the differences in their optical properties. The difference in the luminescence efficiency between 2 and 3 is attributed to the presence of π…π stacking and the different luminescence processes.

Download Full-text

Z/E-Isomerism of 3-[4-(dimethylamino)phenyl]-2-(2,4,6-tribromophenyl)acrylonitrile: crystal structures and secondary intermolecular interactions

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229617017648 ◽

2018 ◽

Vol 74 (1) ◽

pp. 69-74

Author(s):

Renuka Devi Tammisetti ◽

Ilya V. Kosilkin ◽

Ilia A. Guzei ◽

Victor N. Khrustalev ◽

Larry Dalton ◽

...

Keyword(s):

Crystal Structure ◽

Density Functional ◽

Crystal Packing ◽

Monoclinic Space Group ◽

X Ray Diffraction ◽

Functional Theory ◽

Triclinic Space Group ◽

Space Group ◽

Total Energies ◽

The Difference

The Z and E isomers of 3-[4-(dimethylamino)phenyl]-2-(2,4,6-tribromophenyl)acrylonitrile, C17H13Br3N2, (1), were obtained simultaneously by a Knoevenagel condensation between 4-(dimethylamino)benzaldehyde and 2-(2,4,6-tribromophenyl)acetonitrile, and were investigated by X-ray diffraction and density functional theory (DFT) quantum-chemical calculations. The (Z)-(1) isomer is monoclinic (space group P21/n, Z′ = 1), whereas the (E)-(1) isomer is triclinic (space group P\overline{1}, Z′ = 2). The two crystallographically-independent molecules of (E)-(1) adopt similar geometries. The corresponding bond lengths and angles in the two isomers of (1) are very similar. The difference in the calculated total energies of isolated molecules of (Z)-(1) and (E)-(1) with DFT-optimized geometries is ∼4.47 kJ mol−1, with the minimum value corresponding to the Z isomer. The crystal structure of (Z)-(1) reveals strong intermolecular nonvalent Br...N [3.100 (2) and 3.216 (3) Å] interactions which link the molecules into layers parallel to (10\overline{1}). In contrast, molecules of (E)-(1) in the crystal are bound to each other by strong nonvalent Br...Br [3.5556 (10) Å] and weak Br...N [3.433 (4) Å] interactions, forming chains propagating along [110]. The crystal packing of (Z)-(1) is denser than that of (E)-(1), implying that the crystal structure realized for (Z)-(1) is more stable than that for (E)-(1).

Download Full-text

First principles analysis of oxygen vacancy formation and migration in Sr2BMoO6 (B = Mg, Co, Ni)

RSC Advances ◽

10.1039/c6ra02297a ◽

2016 ◽

Vol 6 (38) ◽

pp. 31968-31975 ◽

Cited By ~ 9

Author(s):

Shuai Zhao ◽

Liguo Gao ◽

Chunfeng Lan ◽

Shyam S. Pandey ◽

Shuzi Hayase ◽

...

Keyword(s):

Density Functional Theory ◽

Oxygen Vacancy ◽

First Principles ◽

Density Functional ◽

Dft Method ◽

Double Perovskites ◽

Functional Theory ◽

Oxygen Vacancy Formation ◽

The Density Functional Theory ◽

And Migration

In this work, we present a detailed first-principles investigation on the stoichiometric and oxygen-deficient structures of double perovskites, Sr2BMoO6 (B = Mg, Co and Ni), using the density functional theory (DFT) method.

Download Full-text

Vibrational Study and Force Field of the Citric Acid Dimer Based on the SQM Methodology

Advances in Physical Chemistry ◽

10.1155/2011/347072 ◽

2011 ◽

Vol 2011 ◽

pp. 1-10 ◽

Cited By ~ 43

Author(s):

Laura Cecilia Bichara ◽

Hernán Enrique Lanús ◽

Evelina Gloria Ferrer ◽

Mónica Beatriz Gramajo ◽

Silvia Antonia Brandán

Keyword(s):

Citric Acid ◽

Force Field ◽

Density Functional ◽

Solid Phase ◽

Dft Method ◽

Electronic Charge ◽

Functional Theory ◽

The Density Functional Theory ◽

Atoms In Molecules Theory ◽

Best Fit

We have carried out a structural and vibrational theoretical study for the citric acid dimer. The Density Functional Theory (DFT) method with the B3LYP/6-31G∗ and B3LYP/6-311++ methods have been used to study its structure and vibrational properties. Then, in order to get a good assignment of the IR and Raman spectra in solid phase of dimer, the best fit possible between the calculated and recorded frequencies was carry out and the force fields were scaled using the Scaled Quantum Mechanic Force Field (SQMFF) methodology. An assignment of the observed spectral features is proposed. A band of medium intensity at 1242 together with a group of weak bands, previously not assigned to the monomer, was in this case assigned to the dimer. Furthermore, the analysis of the Natural Bond Orbitals (NBOs) and the topological properties of electronic charge density by employing Bader's Atoms in Molecules theory (AIM) for the dimer were carried out to study the charge transference interactions of the compound.

Download Full-text

Chloroquine drug and Graphene complex for treatment of COVID-19

10.21203/rs.3.rs-29418/v1 ◽

2020 ◽

Author(s):

Saeedeh Mohammadi ◽

Mohammad Esmailpour ◽

Mina Mohammadi

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Energy Gap ◽

Dft Method ◽

Complex State ◽

Functional Theory ◽

The Density Functional Theory ◽

Structural And Electrical Properties ◽

Suitable Structure ◽

Drug Complex

Abstract This paper is a new step in helping the treatment of coronavirus by improving the performance of chloroquine drug. For this purpose, we propose a complex of chloroquine drug with graphene nanoribbon (GNR) scheme. We compute the structural and electrical properties and absorption of chloroquine (C18H26ClN3) and GNR complex using the density functional theory (DFT) method. By creating a drug and GNR complex, the density of states of electrons increases and the energy gap decreases compared to the chloroquine. Also, using absorption calculations and spectrums such as infrared and UV-Vis spectra, we showed that GNR is a suitable structure for creating chloroquine drug complex. Our results show that the dipole moment, global softness and electrophilicity for the drug complex increases compared to the non-complex state. Our calculations can be useful for increasing performance and reducing the side effects of chloroquine, and thus can be effective in treating coronavirus.

Download Full-text