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1.
Acta Chim Slov ; 63(3): 619-26, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27640389

RESUMO

The title compound (Z)-5-(4-chlorobenzylidene)-3-(2-ethoxyphenyl)-2-thioxothiazolidin-4-one (CBBTZ) was characterized by X-ray single crystal diffraction, 1H NMR and 13C NMR spectra. Theoretical investigations were carried out using HF and DFT levels of theory at 6-31G(d,p) basis set. The X-ray structure is compared with that computed. The calculated geometrical parameters are in good agreement with those determined by X-ray diffraction. The dihedral angle between the two benzene rings is 16.89(5)° indicating that the structure is non planar. The molecule exhibits intraand intermolecular contacts of type C-H···O, C-H···S and C-H···Cl. The intercontacts in the crystal structure are explored using Hirshfeld surfaces analysis method.

2.
Molecules ; 20(3): 4042-54, 2015 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25741898

RESUMO

This work concerns a comparison of experimental and theoretical results of the electron charge density distribution and the electrostatic potential around the m-nitrophenol molecule (m-NPH) known for its interesting physical characteristics. The molecular experimental results have been obtained from a high-resolution X-ray diffraction study. Theoretical investigations were performed using the Density Functional Theory at B3LYP level of theory at 6-31G* in the Gaussian program. The multipolar model of Hansen and Coppens was used for the experimental electron charge density distribution around the molecule, while we used the DFT methods for the theoretical calculations. The electron charge density obtained in both methods allowed us to find out different molecular properties such us the electrostatic potential and the dipole moment, which were finally subject to a comparison leading to a good match obtained between both methods. The intramolecular charge transfer has also been confirmed by an HOMO-LUMO analysis.


Assuntos
Nitrofenóis/química , Teoria Quântica , Eletricidade Estática , Termodinâmica , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Difração de Raios X
3.
ACS Omega ; 9(27): 29263-29273, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39005796

RESUMO

In this work, we use a combination of dispersion-corrected density functional theory (DFT-D3) and the TiberCAD framework for the first time to investigate a newly designed and synthesized class of (C6H10N2)[CuCl4] 2D-type perovskite. The inter- and intra-atomic reorganization in the crystal packing and the type of interaction forming in the active area have been discussed via Hirshfeld surface (HS) analyses. A distinct charge transfer from CuCl4 to [C6H10N2] is identified by frontier molecular orbitals (FMOs) and density of states (DOS). This newly designed narrow-band gap small-molecule perovskite, with an energy gap (E g) of 2.11 eV, exhibits a higher fill factor (FF = 81.34%), leading to an open-circuit voltage (V oc) of 1.738 V and a power conversion efficiency (PCE) approaching ∼10.20%. The interaction between a donor (D) and an acceptor (A) results in a charge transfer complex (CT) through the formation of hydrogen bonds (Cl-H), as revealed by QTAIM analysis. These findings were further supported by 2D-LOL and 3D-ELF analyses by visualizing excess electrons surrounding the acceptor entity. Finally, we performed numerical simulations of solar cell structures using TiberCAD software.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124093, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38428162

RESUMO

Theoretical computations of pyrimidine-based azo dyes were performed by the DFT approach using the B3LYP/6 - 31G(d,p) basis set. The molecules were optimized based on the same basis set by calculating the minimum energy. FMOs, DOS and GCRD were computed for kinetic stability and chemical reactivity of the selected compounds. The MEP surface was studied to locate nucleophilic and electrophilic attack zones. The energy gap was carefully studied for pyrimidine-based azo dyes. Vibrational spectroscopy was studied in the most prominent regions with respect to PED assignments. Similarly, the UV-Vis absorption technique was calculated using the TD-DFT approach in different solvent media. The electronic structure of each atom in a molecule was examined via the electron localization function (ELF) and localized orbital locator (LOL). Non-covalent interactions were explored using reduced density gradient analysis. The combination of experimental and theoretical data allowed us to correlate the structural modifications with the observed photophysical properties, facilitating the design of azo dyes with tailored characteristics. This work contributes to the fundamental understanding of azo dyes and offers a foundation for the development of new materials with enhanced photophysical and electronic properties.

5.
Heliyon ; 9(11): e21315, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37954314

RESUMO

The potential of 2,6-bis(4-fluorophenyl)-3,3-dimethylpiperidin-4-one (BFDP) as an anti-Parkinson's, anti-lung cancer, and anti-human infectious agent was extensively assessed in the current study. To accomplish this, the compound BFDP was synthesised and analysed using several spectroscopic approaches, such as NMR, mass and FT-IR spectral studies. The computational calculations for the molecule were carried out using density functional theory (DFT) at the B3LYP/6-311G++ (d,p) level of theory. A X-ray diffraction (XRD) study allows us to analyse the crystalline structure of our BFDP molecule. Intermolecular interactions were assessed using 3D Hirshfeld surfaces (3D-HS) and 2D fingerprint plots. AIM and NCI-RDG were done using quantum calculations and the DFT technique, and topological ELF and LOL, as well as vibrational parameters, have been obtained. The thermodynamic and thermal properties of the BFDP compound were determined. To investigate the pharmacokinetic characteristics of BFDP, a molecular docking study and an in silico ADMET study were done.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123130, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37517274

RESUMO

This paper reports on a study of the photophysical properties, density functional theory (DFT) calculations, infrared (IR), ultraviolet (UV) and nuclear magnetic resonance (NMR) spectroscopic techniques of a series of aurone compounds. The photophysical properties were investigated using UV absorption and fluorescence spectroscopy in a dimethyl sulfoxide (DMSO) solution. Furthermore, the fluorescence quantum yields of the target compounds (1-24) were also investigated. Remarkably, these compounds revealed high quantum yields (Φ = 0.001-0.729) as compared to the already existing aurones in literature. The DFT calculations were performed to elucidate the electronic structure, energy levels and draw a comparison between experimental and theoretical findings. The simulated properties such as molecular frontier orbitals, the density of states, reactivity descriptors (GCRD), electrostatic potential distribution, transition density matrix, electron localization function (ELF) and localized orbital locator (LOL) have been calculated using DFT. The DFT calculations provided insight into the electronic structure and energy levels of the aurone compounds, while the IR and UV spectroscopy results shed light on their functional groups and electronic transitions, respectively. The results of this study contribute to a better understanding of the photophysical properties of aurone compounds and suggest their potential use in technological applications.

7.
Molecules ; 17(3): 3501-9, 2012 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-22430117

RESUMO

As part of our project devoted to the synthesis of heterocycles including thiazole rings, some new 5-arylidene-2-thioxo-3-N-arylthiazolidin-4-ones were synthesized by Knoevenagel condensation. An interesting feature of these compounds is that their chirality is induced by that of their 3-N-(2-alkyloxyaryl)-2-thioxothiazolidin-4-one precursors, which in turn is due to the presence of a C2 axis of chirality. These new compounds were characterized by spectroscopic methods (IR, 1H-NMR, 13C-NMR). The structure of compound (Z)-(2g) was further determined by X-ray diffraction.


Assuntos
Tiazóis/química , Tiazóis/síntese química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Difração de Raios X
8.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 12): 1832-1836, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33520263

RESUMO

The thia-zolo[3,4-a]benzimidazole fused-ring system in the title compound, C14H8N2OS2, is nearly planar, the r.m.s. deviation being 0.0073 Å. The thia-zolo-benzimidazole-2-thione system is almost in the same plane as the furan-2-yl-methyl-ene moiety, with a dihedral angle of 5.6 (2)° between the two least-squares planes. In the crystal, adjacent mol-ecules are connected by weak inter-molecular inter-actions (C-H⋯N and slipped π-π stacking) into a three-dimensional network. The nature of the inter-molecular inter-actions was also qu-anti-fied by Hirshfeld surface analysis. DFT analysis indicates a good agreement of the experimentally determined and the theoretically calculated mol-ecular structures.

9.
Heliyon ; 6(12): e05754, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33385082

RESUMO

We reported an experimental and theoretical spectroscopic studies of (2Z,5Z)-5-(4-nitrobenzylidene)-3-N (2-methoxyphenyl)-2-N' (2-methoxyphenylimino) thiazolidin-4-one (C24H19N3O5S) molecule, using FT-IR, NMR spectroscopy, and density functional theory (DFT) via time-dependent schema (TD-DFT) respectively. The molecular inter-contacts were explored using Hirshfeld surfaces (HS) analysis method. Vibrational frequencies, gauge-independent atomic orbital (GIAO)1H and13C NMR chemical shift values and frontier molecular orbitals (FMOs) have been calculated from the optimized structure of the molecule by DFT/B3LYP functional with 6-31G(d, p) basis set. Our theoretical results show a good agreement with the experimental data. The calculated UV-visible spectrum employing TD-DFT shows electronic transitions at 388 nm and 495 nm. To get insight on the charge interaction happening inside the molecule, HOMO and LUMO were scrutinized and their calculated energy gap was found to be 2.96 eV. The molecular docking was analyzed via interplay study ofacetyl cholinesterase, and Butyrylcholinesterase using molecular docking methodology.

10.
Acta Chim Slov ; 66(2): 490-500, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33855506

RESUMO

In this paper we report the synthesis and characterization of the (Z)-3-N-(ethyl)-2-N'-((3-methoxyphenyl)imino)thiazolidine- 4-one by means of FT-IR, 1H and 13C NMR and by single crystal X-ray diffraction. The experimental determination of the crystal structure of the compound has been achieved using X-ray diffraction data. The important characteristic of the structure is the existence of a dihedral angle formed by the benzene and thiazolidinone rings being equal to 86.0° indicating an absence of α-α stacking as well as that the structure is non planar. In the crystal, the molecules are linked by C-H···O and C-H···N hydrogen bonds, these bonds being responsible for the three-dimensional molecular structure packing. In order to compare the experimental results with those of the theoretical calculation, quantum chemical DFT calculations were carried out using B3LYP/6-311G(d,p) basis set. In this context, the molecular electrostatic potential around the molecule and HOMO-LUMO energy levels were also computed. The dipole moment orientations were determined in order to understand the nature of inter- and intramolecular charge transfer. Finally, the stability of the title compound was confirmed throughout the calculation of the chemical reactivity descriptors.

11.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 4): 511-514, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28435709

RESUMO

In the title compound, C24H19N3O5S, the thia-zole ring (r.m.s. deviation = 0.012 Å) displays a planar geometry and is surrounded by three fragments, two meth-oxy-phenyl and one nitro-phenyl. The thia-zole ring is almost in the same plane as the nitro-phenyl ring, making a dihedral angle of 20.92 (6)°. The two meth-oxy-phenyl groups are perpendicular to the thia-zole ring [dihedral angles of 79.29 (6) and 71.31 (7)° and make a dihedral angle of 68.59 (7)°. The mol-ecule exists in an Z,Z conformation with respect to the C=N imine bond. In the crystal, a series of C-H⋯N, C-H⋯O and C-H⋯S hydrogen bonds, augmented by several π-π(ring) inter-actions, produce a three-dimensional architecture of mol-ecules stacked along the b-axis direction. The experimentally derived structure is compered with that calculated theoretically using DFT(B3YLP) methods.

12.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 2): 173-176, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28217336

RESUMO

In the title compound, C18H20N4O3S, the 1,2,4-triazole ring is twisted with respect to the mean plane of quinoline moiety at 65.24 (4)°. In the crystal, mol-ecules are linked by weak C-H⋯O and C-H⋯N hydrogen bonds, forming the three-dimensional supra-molecular packing. π-π stacking between the quinoline ring systems of neighbouring mol-ecules is also observed, the centroid-to-centroid distance being 3.6169 (6) Å. Hirshfeld surface (HS) analyses were performed.

13.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 2): 155-7, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26958377

RESUMO

In the title compound, C26H21N3O5S, the thia-zole ring is nearly planar with a maximum deviation of 0.017 (2) Å, and is twisted with respect to the three benzene rings, making dihedral angles of 25.52 (12), 85.77 (12) and 81.85 (13)°. In the crystal, weak C-H⋯O hydrogen bonds and C-H⋯π inter-actions link the mol-ecules into a three-dimensional supra-molecular architecture. Aromatic π-π stacking is also observed between the parallel nitro-benzene rings of neighbouring mol-ecules, the centroid-to-centroid distance being 3.5872 (15) Å.

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