Synthesis, characterisation, optical properties and theoretical calculations of a new fluorescent heterocyclic system: 3H-benzo[a]pyrazolo[3,4-j]acridine

2017 ◽  
Vol 41 (7) ◽  
pp. 371-375 ◽  
Author(s):  
Hamideh Alipoor ◽  
Mehdi Pordel ◽  
Ali Morsali
Keyword(s):  
Density Functional Theory ◽  
Optical Properties ◽  
Density Functional ◽  
Fluorescent Dyes ◽  
Analytical Data ◽  
Density Functional Theory Method ◽  
Basis Set ◽  
Quantum Yields ◽  
Functional Theory ◽  
Fluorescence Characteristics

Four new fluorescent dyes derived from the 3 H-benzo[ a]pyrazolo[3,4- j]acridine system were synthesised and fully characterised by 1H NMR, 13C NMR, mass and analytical data. These new fluorophores were prepared from the reaction of 1-alkyl-5-nitro-1 H-indazoles with 1-naphthylacetonitrile via nucleophilic substitution of hydrogen, in high yields. The optical properties of the dyes were also investigated and the results revealed that, in some cases, they have higher quantum yields compared with well-known fluorescent dyes such as fluorescein. Solvent effects on the fluorescence characteristics of the four compounds indicated that the emission wavelength is red-shifted with increasing solvent polarity. Furthermore, density functional theory calculations using the B3LYP hybrid functional and the 6-311++G(d,p) basis set provided the optimised geometries and relevant frontier orbitals of the compounds. Calculated electronic absorption spectra were also obtained using the time-dependent density functional theory method.

Synthesis of New Dyes from Imidazo[1,2-a]Pyridine: Tautomerism, Spectroscopic Characterisation, DFT/TD-DFT Calculations, Atoms in Molecules Analyses and Antibacterial Activities

2017 ◽  
Vol 41 (3) ◽  
pp. 143-148 ◽  
Author(s):  
Samaneh Mohammadi ◽  
Mehdi Pordel ◽  
Sadegh Allameh ◽  
Hamed Chegini
Keyword(s):  
Density Functional Theory ◽  
Antibacterial Activity ◽  
Optical Properties ◽  
Density Functional ◽  
Bacterial Species ◽  
Analytical Data ◽  
Density Functional Theory Method ◽  
Antibacterial Activities ◽  
Atoms In Molecules ◽  
Functional Theory

The synthesis, optical properties, theoretical calculations and antibacterial activity of a series of new heterocyclic dyes from imidazo[1,2-a] pyridine are described. The key intermediate 2-[3-(hydroxyimino)imidazo[1,2-a]pyridin-2(3H)-ylidene]malononitrile was obtained via the nucleophilic substitution of hydrogen in 3-nitroimidazo[1,2-a]pyridine with malononitrile in basic methanol solution. Tautomerism, oxidation and alkylation studies on the dye led to the synthesis of new heterocyclic indigo-coloured, purple, and orange dyes in good yields. The structures of all newly synthesised compounds were confirmed by spectral and analytical data. The optical properties of the dyes were spectrally characterised and shown to exhibit interesting photophysical properties including high extinction coefficients. Density functional theory calculations of the dyes were performed to provide the optimised geometries and relevant frontier orbitals. Calculated electronic absorption spectra were also obtained by the time-dependent density functional theory method. In addition, electrostatic potential maps and electron density maps of the dyes were evaluated by AIM (atoms in molecules) analysis. Moreover, the new dyes exhibited potent antibacterial activity and their antibacterial activities (MIC) against Gram-positive and Gram-negative bacterial species were determined.

scholarly journals Ultrasound Assisted Synthesis, Molecular Structure,UV-Visible Assignments, MEP and Mulliken Charges Study of (E)-3-(4-chlorophenyl)-1-(4-methoxyphenyl) prop-2-en-1-one: Experimental and DFT Correlational

2021 ◽  
Vol 18 (1) ◽  
pp. 86-96
Author(s):  
Rohit S. Shinde
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Density Functional Theory Method ◽  
Atomic Charge ◽  
Dft Method ◽  
Basis Set ◽  
Geometrical Parameters ◽  
Functional Theory ◽  
Vibrational Assignments ◽  
Uv Visible

Present investigation deals with the synthesis and density functional theory study (DFT) of a chalcone derivative; (E)-3-(4-chlorophenyl)-1-(4-methoxyphenyl)prop-2-en-1-one (CPMPP). The synthesis of a CPMPP has been carried out by the reaction of 4-methoxyacetophenone and 4-chlorobenzalehyde in ethanol at 30 ℃ under ultrasound irradiation. The structure of a synthesized chalcone is affirmed on the basis of FT-IT, 1H NMR and 13C NMR. The geometry of a CPMPP is optimized by using the density functional theory method at the B3LYP/6-31G(d,p) basis set. The optimized geometrical parameters like bond length and bond angles have been computed. The absorption energies, oscillator strength, and electronic transitions have been derived at the TD-DFT method at the B3LYP/6-31G(d,p) level of theory for B3LYP/6-31G(d p) optimized geometries. The effect of polarity on the absorption energies is discussed by computing UV-visible results in dichloromethane (DCM). Since theoretically obtained wavenumbers are typically higher than experimental wavenumbers, computed wavenumbers were scaled with a scaling factor, and vibrational assignments were made by comparing experimental wavenumbers to scaled theoretical wavenumbers. Quantum chemical parameters have been determined and examined. Molecular electrostatic potential (MEP) surface plot analysis has been carried out at the same level of theory. Mulliken atomic charge study is also discussed in the present study.

scholarly journals Raman Spectroscopy Of Fullerene-Like Molecules Of Silicon Dioxide (SiO2)N(H2O)N/2

2016 ◽  
Vol 17 (3) ◽  
pp. 401-406
Author(s):  
O.V. Filonenko
Keyword(s):  
Density Functional Theory ◽  
Raman Spectroscopy ◽  
Silicon Dioxide ◽  
Density Functional ◽  
Density Functional Theory Method ◽  
Basis Set ◽  
Theory Method ◽  
Cyclic Structure ◽  
Functional Theory ◽  
Exchange Correlation

The Raman spectra of monosilicic, disilicic acid molecules, tetra- and pentasilicic acid molecules with cyclic structure, cage-like okta- and dekasilicic asid molecules, and of fullerene-like molecule (SiO2)N(H2O)N/2 have been calculated using density functional theory method (exchange-correlation functional B3LYP and basis set 6-31G (d, p)) and assignment of frequencies in conformity with the shape fluctuations have been executed.

scholarly journals NBO, nonlinear optical and thermodynamic properties of 10-Acetyl-10H-phenothiazine 5-oxide

BIBECHANA ◽  
2017 ◽  
Vol 15 ◽  
pp. 131-139
Author(s):  
Bhawani Datt Joshi ◽  
Manoj Kumar Chaudhary
Keyword(s):  
Density Functional Theory ◽  
Optical Properties ◽  
Thermodynamic Properties ◽  
Density Functional ◽  
Nonlinear Optical ◽  
Natural Bond Orbital ◽  
Nbo Analysis ◽  
Basis Set ◽  
Functional Theory ◽  
Density Functional Theory Level

In this paper, natural bond orbital (NBO) analysis, nonlinear optical and the thermodynamic properties of 10-Acetyl-10H-phenothiazine 5-oxide have been analyzed by employing density functional theory level employing 6-311++G(d,p) basis set. NBO analysis reveals that the intra- intermolecular charge transfer occurs within the molecule leading to the stabilization. The predicted nonlinear optical properties (NLO) like; polarizability and first hyperpolarizabiliy support that the molecule could attract the interests for future investigation.BIBECHANA 15 (2018) 131-139

Basis Set Effects in Density Functional Theory Calculation of Muoniated Cytosine Nucleobase

2020 ◽  
Vol 860 ◽  
pp. 282-287
Author(s):  
Wan Nurfadhilah Zaharim ◽  
Shukri Sulaiman ◽  
Saidah Sakinah Mohd Tajudin ◽  
Siti Nuramira Abu Bakar ◽  
Nur Eliana Ismail ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Total Energy ◽  
Density Functional ◽  
Density Functional Theory Calculation ◽  
Geometry Optimization ◽  
Density Functional Theory Method ◽  
Basis Set ◽  
Basis Sets ◽  
Functional Theory ◽  
Muonium Hyperfine

The Density Functional Theory method was employed to investigate the electronic structure and muonium hyperfine interaction of muonium trapped near carbon atom labelled as '5' in cytosine nucleobase. Eighteen different basis sets in combination with B3LYP functional were examined in geometry optimization calculations on the muoniated radical. There are significant quantitative differences in the calculated total energy. The employment of basis set that does not include polarization function produces an optimized structure with high total energy. The 6-311++G(d,p) basis set yielded the lowest total energy as compared to other basis sets. The bond order of muonium trapped at C5 atom is in the range of 0.841 to 0.862. The 6-31G basis set produced the muonium Fermi contact coupling constant that is the closest to the experimental value.

scholarly journals DFT Exploration on Molecular Characteristics of 6-Methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxylate

2021 ◽  
Vol 7 (1) ◽  
pp. 717-720
Author(s):  
Abhijit R. Bukane ◽  
Bapu S. Jagdale
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Sulfamic Acid ◽  
Density Functional Theory Method ◽  
Atomic Charge ◽  
Catalytic Amount ◽  
Basis Set ◽  
Molecular Characteristics ◽  
Geometrical Parameters ◽  
Functional Theory

Present investigation deals with the synthesis and density functional theory study (DFT) of a Biginelli adduct; 6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxylate (MOPTHPC). The synthesis of a MOPTHPC has been carried out by the reaction of benzaldehyde, ethyl acetoacetate and urea in ethanol 70-80 ℃ under stirring condition in presence of catalytic amount of sulfamic acid. The structure of a synthesized chalcone is affirmed on the basis of 1H NMR and 13C NMR. The geometry of a MOPTHPC is optimized by using the density functional theory method at the B3LYP/6-311G(d,p) basis set. The optimized geometrical parameters like bond length and bond angles have been computed. Quantum chemical parameters have been determined and examined. Molecular electrostatic surface potential (MESP) surface plot analysis has been carried out at the same level of theory. Mulliken atomic charge study is also discussed in the present study.

scholarly journals Electronic Structure, Nonlinear Optical Properties, and Vibrational Analysis of Gemifloxacin by Density Functional Theory

2012 ◽  
Vol 27 ◽  
pp. 185-206 ◽  
Author(s):  
Shamoon Ahmad Siddiqui ◽  
Tabish Rasheed ◽  
Mohd Faisal ◽  
Anoop Kumar Pandey ◽  
Sher Bahadar Khan
Keyword(s):  
Density Functional Theory ◽  
Optical Properties ◽  
Density Functional ◽  
Normal Modes ◽  
Vibrational Analysis ◽  
Basis Set ◽  
Functional Theory ◽  
Linear Optical Properties ◽  
Equilibrium Geometries ◽  
Homo Lumo

The non-linear optical properties of gemifloxacin (C18H20FN5O4) have been examined using density functional theory (DFT). The molecular HOMO, LUMO composition, their respective energy gaps, MESP contours/surfaces have also been drawn to explain the activity of gemifloxacin. The equilibrium geometries and harmonic frequencies of title molecule was determined and analyzed at DFT/B3LYP level employing the 6-31G(d,p) basis set. The skeleton of both the optimized molecules is non-planar. In general, a good agreement between experimental and calculated normal modes of vibrations has been observed.

scholarly journals Synthesis, Antioxidant Activity and DFT Study of Some Novel N-Methylated Indole Incorporating Isoxazole Moieties

2019 ◽  
Vol 32 (2) ◽  
pp. 244-248
Author(s):  
J. Jani Matilda ◽  
T.F. Abbs Fen Reji
Keyword(s):  
Density Functional ◽  
Structural Parameters ◽  
Analytical Data ◽  
Radical Scavenging ◽  
Density Functional Theory Method ◽  
Basis Set ◽  
Anticancer Activities ◽  
Functional Theory ◽  
Radical Scavenging Ability ◽  
Isoxazole Derivatives

A novel series of indolyl isoxazole derivatives were synthesized and the structure of the products is confirmed on the basis of IR, 1H NMR, MS and analytical data. The synthesized compounds were evaluated for their antioxidant and anticancer activities. The results revealed clearly those compounds 4b and 4d exhibited better radical scavenging ability. The optimized structural parameters of all compounds was carried out at the B3LYP/6-311++G (d, p) level of DFT basis set implemented in Gaussian 09 program package. Theoretical calculation of the title compounds were carried out using density functional theory method (DFT).

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