Spectroscopic investigation of 2-(4-benzoyl-1,5-diphenyl-1H-pyrazol-3-yl)-4H-naphto[2,3-d][1,3]oxazin-4-one molecule

2017 ◽  
Vol 16 (05) ◽  
pp. 1750039
Author(s):  
Yusuf Sert ◽  
Mehmet Gümüş ◽  
Volkan Kamaci ◽  
Halil Gökce ◽  
İbrahim Kani ◽  
...  
Keyword(s):  
Molecular Orbital ◽  
Title Compound ◽  
Chemical Shifts ◽  
Basis Set ◽  
Potential Energy Distribution ◽  
Distribution Analysis ◽  
Laser Raman ◽  
Laser Raman Spectra ◽  
Software Program ◽  
Lowest Unoccupied Molecular Orbital

In this present study, the experimental and theoretical vibrational frequencies of an important pharmacological molecule 2-(4-benzoyl-1,5-diphenyl-1[Formula: see text]-pyrazol-3-yl)-4[Formula: see text]-naphto[2,3-[Formula: see text]][1,3]oxazin-4-one have been researched. The experimental FT-IR and laser-Raman spectra of the title compound have been taken in the region (4000–400[Formula: see text]cm[Formula: see text]) and (4000–100[Formula: see text]cm[Formula: see text]), respectively. The vibrational modes and optimized structure parameters have been computed by using DFT/B3LYP methods with 6-311[Formula: see text]G(d,p) basis set. In our calculations, Gaussian 09W software program has been used. Assignments of theoretical vibrations have been obtained by potential energy distribution analysis using VEDA 4 software program. This program is important because it performs assignments with 10% precision. We have obtained a fairly good agreement between experimental and theoretically obtained results, and these results have supported the literature. Additionally, we have examined the highest occupied molecular orbital and the lowest unoccupied molecular orbital energies, the other related molecular energy values, nuclear magnetic resonance ([Formula: see text]C and 1H-proton) chemical shifts, and UV–Vis wavelengths (electronic absorption wavelengths of the title compound) by using the mentioned calculation level. The nonlinear optical properties of the title compound have also been determined by using DFT/B3LYP/6-311[Formula: see text]G(d,p) level.

Experimental (FT-IR, Laser-Raman and NMR) and theoretical comparative study on 2-benzylsulfanyl-4-pentyl-6-(phenylsulfanyl)pyrimidine-5-carbonitrile, a potential bioactive agent

2018 ◽  
Vol 17 (05) ◽  
pp. 1850035 ◽  
Author(s):  
Lamya H. Al-Wahaibi ◽  
Nuri Öztürk ◽  
Hanan M. Hassan ◽  
Yusuf Sert ◽  
Ali A. El-Emam ◽  
...  
Keyword(s):  
Molecular Orbital ◽  
Chemical Shifts ◽  
Pyrimidine Derivative ◽  
Basis Set ◽  
Potential Energy Distribution ◽  
Laser Raman ◽  
Highest Occupied Molecular Orbital ◽  
Laser Raman Spectra ◽  
Lowest Unoccupied Molecular Orbital ◽  
Ft Ir

In this paper, the experimental and theoretical vibrational frequencies of a potential bioactive pyrimidine derivative molecule named 2-benzylsulfanyl-4-pentyl-6-(phenylsulfanyl)pyrimidine-5-carbonitrile has been investigated. The experimental FT-IR and Laser-Raman spectra of the studied molecule are in the region (4000–400[Formula: see text]cm[Formula: see text] and (4000–100[Formula: see text]cm[Formula: see text], respectively, in gas phase. The vibrational modes and optimized ideal structure parameters(bond lengths, bond angles and selected dihedral angles) were calculated by using DFT/B3LYP, DFT/BHandHLYP and DFT/PBE1PBE methods with 6-311[Formula: see text]G(d,p) basis set. The theoretical mode assignments have been obtained by using potential energy distribution (PED) with the VEDA4 software program. Additionally, infrared and Raman intensities, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) energies and their clouds, and other related molecular properties were calculated and evaluated. The proton (1H) and carbon-13 ([Formula: see text]C) nuclear magnetic resonance (NMR) chemical shifts have been investigated for the title molecule, both experimentally (in DMSO-d[Formula: see text] and theoretically (in vacuum and DMSO). The thermodynamic properties of the tile compound have been investigated using the mentioned theoretical computational methods. The results revealed that there isgood agreement between experimental and theoretical results and these results have supported the related literature.

scholarly journals Spectroscopic Investigations and DFT Calculations on 3-(Diacetylamino)-2-ethyl-3H-quinazolin-4-one

2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Yusuf Sert ◽  
Fatih Ucun ◽  
Gamal A. El-Hiti ◽  
Keith Smith ◽  
Amany S. Hegazy
Keyword(s):  
Molecular Orbital ◽  
Density Functional ◽  
Solid Phase ◽  
Vibrational Frequencies ◽  
Geometric Parameters ◽  
Basis Set ◽  
Potential Energy Distribution ◽  
Laser Raman ◽  
Quantum Chemical Methods ◽  
Lowest Unoccupied Molecular Orbital

The theoretical and experimental vibrational frequencies of 3-(diacetylamino)-2-ethyl-3H-quinazolin-4-one (2) were investigated. The experimental Laser-Raman spectrum (4000–100 cm−1) and FT-IR spectrum (4000–400 cm−1) of the newly synthesized compound were recorded in the solid phase. Both the theoretical vibrational frequencies and the optimized geometric parameters such as bond lengths and bond angles have for the first time been calculated using density functional theory (DFT/B3LYP and DFT/M06-2X) quantum chemical methods with the 6-311++G(d,p) basis set using Gaussian 03 software. The vibrational frequencies were assigned with the help of potential energy distribution (PED) analysis using VEDA 4 software. The calculated vibrational frequencies and the optimized geometric parameters were found to be in good agreement with the corresponding reported experimental data. Also, the energies of the lowest unoccupied molecular orbital (LUMO), highest occupied molecular orbital (HOMO), and other related molecular energies for 3-(diacetylamino)-2-ethyl-3H-quinazolin-4-one (2) have been investigated using the same computational methods.

scholarly journals Structure, Electronic And Vibrational Study of 7-Methyl-2,3-Dihydro-(1,3)Thiazolo(3,2-A) Pyrimidin-5-One by Using Density Functional Theory

2018 ◽  
Vol 22 (2) ◽  
pp. 1-11
Author(s):  
Bhawani Datt Joshi ◽  
Janga Bahadur Khadka ◽  
Atamram Bhatt
Keyword(s):  
Density Functional Theory ◽  
Molecular Orbital ◽  
Density Functional ◽  
Basis Set ◽  
Orbital Energy ◽  
Potential Energy Distribution ◽  
Functional Theory ◽  
Hartree Fock ◽  
Solvent Phase ◽  
Lowest Unoccupied Molecular Orbital

 We have presented molecular structure and vibrational wavenumber assignments of 7-methyl-2,3-dihydro-(1,3)thiazolo(3,2-a)pyrimidin-5-one. Both ab initio Hartree-Fock and density functional theory employing 6-311++G(d,p) basis set have been used for the calculations. The scaled values of the calculated vibrational frequencies were used for assignments on the basis of potential energy distribution. The structure-activity relation has been interpreted by mapping molecular electrostatic potential surface. Electronic properties have been analyzed by using time dependent density functional theory (TD-DFT) for both gaseous and solvent phase. The calculated HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) energy values show that the charge transfer occurs within the molecule. Journal of Institute of Science and TechnologyVolume 22, Issue 2, January 2018, Page: 1-11 

Experimental (FT-IR, Laser-Raman and NMR) and theoretical spectroscopic analysis of 3-[(N-methylanilino)methyl]-5-(thiophen-2-yl)-1,3,4-oxadiazole-2(3H)-thione

2017 ◽  
Vol 16 (03) ◽  
pp. 1750024 ◽  
Author(s):  
Yusuf Sert ◽  
Nuri Öztürk ◽  
Fatmah A. M. Al-Omary ◽  
Can Alaşalvar ◽  
Mona M. Al-Shehri ◽  
...  
Keyword(s):  
Molecular Orbital ◽  
Chemical Shifts ◽  
Molecular Structures ◽  
Basis Set ◽  
Spectroscopic Techniques ◽  
Nmr Chemical Shifts ◽  
Laser Raman ◽  
Ft Ir ◽  
Experimental Values ◽  
Vibrational Wavenumbers

The structure of a potential bioactive agent namely, 3-[([Formula: see text]-methylanilino)methyl]-5-(thiophen-2-yl)-1,3,4-oxadiazole-2(3[Formula: see text]-thione was characterized by proton and carbon-13 nuclear magnetic resonance (NMR) chemical shifts, Fourier transform infrared (FT-IR) and Laser-Raman spectroscopic techniques. The quantum chemical computations of molecular structures (disorder I and disorder II forms), vibrational wavenumbers, carbon-13 and proton chemical shifts and UV-Vis spectroscopic parameters have been performed with DFT/B3LYP method at 6-311[Formula: see text]G(d,p) basis set. The highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), nonlinear optical (NLO) properties and natural bond orbital (NBO) analyses have been theoretically examined with the mentioned calculation level. The calculated values have been compared with the recorded experimental data. The computed molecular geometric parameters, vibrational wavenumbers, NMR chemical shifts, and UV-Vis wavelengths have been found to be in a good harmony with the experimental values and spectral results of similar structures in the literature. We believe that the work will be of considerable interest to anyone working in the area of theoretical chemistry, whether in industry or academics.

scholarly journals Synthesis and vibrational spectral (FT-IR, FT-Raman) studies, NLO properties & NBO analysis of (E)-N'(thiophen-2yl methylene)isonicotinohydrazide using quantum chemical method

2018 ◽  
Vol 6 (1) ◽  
pp. 53
Author(s):  
Nathiya A ◽  
Saleem H ◽  
Bharanidharan Bharani ◽  
Suresh M
Keyword(s):  
Molecular Orbital ◽  
Title Compound ◽  
Solid Phase ◽  
Nbo Analysis ◽  
Basis Set ◽  
Excitation Energies ◽  
Charge Delocalization ◽  
Nlo Properties ◽  
Ft Ir ◽  
Ft Raman

FT-IR (4000-400 cm-1) and FT-Raman (3500-50 cm-1) spectra of (E)-N'(thiophen-2yl methylene)isonicotinohydrazide (TMINH) molecule was recorded in solid phase. The optimized geometry was calculated by B3LYP method with 6-311++G(d,p) basis set. The harmonic vibrational frequencies, infrared (IR) intensities and Raman scattering activities of the title compound were performed at same level of theory. The complete vibrational assignments were performed on the basis of the Total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The calculated first hyperpolarizability may be attractive for further studies on non-linear optical (NLO) properties of material. Stability of the molecule arising from hyperconjugative interaction and charge delocalization was analyzed using natural bond orbital (NBO) analysis. Highest occupied molecular orbital-Lowest unoccupied molecular orbital (HOMO-LUMO) energy gap explains the eventual charge transfer interactions taking place within the title molecule. A study on the electronic properties, such as excitation energies and wavelengths, were performed by time-dependent (TD-DFT) approach. Molecular electrostatic potential (MEP) provides the information on the electrophilic, nucleophilic and free radical prone reactive sites of the molecule. The thermodynamic properties such as heat capacity, entropy and enthalpy of the title compound were calculated at different temperatures in gas phase. 1H and 13C-NMR chemical shifts of the molecule were calculated using Gauge-independent atomic orbital (GIAO) method.To establish information about the interactions between human cytochrome protein and this novel compound theoretically, docking studies were carried out using Schrödinger software.

scholarly journals Crystal Structure, Hirshfeld Surface and Frontier Molecular Orbital Analyses of N-[2-(trifluoromethyl)phenyl]succinamic Acid

2020 ◽  
Vol 32 (12) ◽  
pp. 3179-3185
Author(s):  
P.A. Suchetan ◽  
S. Naveen ◽  
N.K. Lokanath ◽  
P. Krishna Murthy ◽  
M.V. Deepa Urs
Keyword(s):  
Hydrogen Bonds ◽  
Molecular Orbital ◽  
Density Functional ◽  
Hirshfeld Surface ◽  
Basis Set ◽  
Frontier Molecular Orbital ◽  
Reactivity Descriptors ◽  
Succinamic Acid ◽  
Highest Occupied Molecular Orbital ◽  
Lowest Unoccupied Molecular Orbital

The ortho-CF3 substituent and the N-H bond are in syn-conformation in N-[2-(trifluoromethyl)phenyl]succinamic acid. In amide and acid functionalities, the carbonyl groups are directed in opposite directions to each other and their related-CH2 groups. syn-Conformation is observed for the acid functionality, where the carbonyl C=O and hydroxyl O-H bonds are directed in the same direction. Three planar fragments comprise of the molecule: aromatic ring (A), core portion -Carm-N(H)-C(=O)-C(H2)-C(H2)(B) and -C(H2)-C(=O)-OH(C). The dihedral angle between a pair of fragments being 48.6(4)º (A and B), 81.6 (4)º (B and C) and 70.5 (5)º (A and C). N-H•••O hydrogen bonds bind the molecules forming C(4) chains in the crystal, and the neighbouring anti-parallel chains are bound by O-H•••O hydrogen bonds resulting in a chair shaped ribbon of one-dimensional nature. The Hirshfeld surface study was carried out, including fingerprint plots. Studies have shown that the interactions with O•••H/H•••O (27.4%), H•••H (27.3%) and H•••F/F•••H (20.2%) substantially added to the surface. Theoretically, the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) and various global reactivity descriptors were also computed by the density functional theory (DFT/B3LYP) approach with a 6-311G(d, p) basis set in the ground state on the geometrically optimized structure in the gas phase.

scholarly journals Theoretical and X-ray diffraction studies of organic photovoltaic compounds

2014 ◽  
Vol 70 (a1) ◽  
pp. C996-C996
Author(s):  
Abdelkader Chouaih ◽  
Salem Yahiaoui ◽  
Nadia Benhalima ◽  
Manel Boulakoud ◽  
Rachida Rahmani ◽  
...  
Keyword(s):  
Molecular Orbital ◽  
Organic Semiconductor ◽  
Density Functional ◽  
Energy Gap ◽  
Three Dimensional ◽  
Basis Set ◽  
X Ray Diffraction ◽  
Hybrid Functional ◽  
X Ray ◽  
Lowest Unoccupied Molecular Orbital

The electronic and structural properties of thiazolic ring derivatives were studied using density functional theory (DFT) and X-ray diffraction in terms of their application as organic semiconductor materials in photovoltaic devices. The B3LYP hybrid functional in combination with Pople type 6-31G(d) basis set with a polarization function was used in order to determine the optimized geometries and the electronic properties of the ground state, while transition energies and excited state properties were obtained from DFT with B3LYP/6-31G(d) calculation. The investigation of thiazolic derivatives formed by the arrangement of several monomeric units revealed that three-dimensional (3D) conjugated architectures present the best geometric and electronic characteristics for use as an organic semiconductor material. The highest occupied molecular orbital (HOMO) . lowest unoccupied molecular orbital (LUMO) energy gap was decreased in 3D structures that extend the absorption spectrum toward longer wavelengths, revealing a feasible intramolecular charge transfer process in these systems. All calculations in this work were performed using the Gaussian 03 W software package.

scholarly journals EXPERIMENTAL CUM THEORETICAL EVALUATION OF MOLECULAR STRUCTURE, VIBRATIONAL SPECTRA, NBO, UV, NMR, OF A BIOACTIVE COMPOUND – PHENOXYACETOHYDRAZIDE

2015 ◽  
Vol 3 (7) ◽  
pp. 103-115
Author(s):  
M. Sangeetha ◽  
R. Mathammal
Keyword(s):  
Molecular Orbital ◽  
Density Functional ◽  
Chemical Shifts ◽  
Atomic Orbital ◽  
Bioactive Compound ◽  
Nbo Analysis ◽  
Basis Set ◽  
Theoretical Evaluation ◽  
Vibrational Assignments ◽  
Key Species

Hydrazide-Hydrazone compounds are key species for a range of bioactivities. The first complete density functional theoretical study of Phenoxyacetohydrazide(PAH) is reported. The normal mode frequencies, intensities and the corresponding vibrational assignments were calculated using the GAUSSIAN 09W set of quantum chemistry codes at the DFT/B3LYP levels of theory using the 6-311++G** basis set. Stability of the molecule arising from hyperconjugative interactions has been probed using NBO analysis. 1H and 13C NMR spectra have been analysed and the chemical shifts were calculated using the gauge independent atomic orbital(GIAO) method. The theoretical UV-Vis spectrum and the electronic properties, such as HOMO(Highest occupied molecular orbital) and LUMO (Lowest unoccupied molecular orbital) were performed by time dependent density functional theory(TD-DFT) approach.

scholarly journals Structural and Vibrational Studies (FT-IR, FT-Raman) of Voglibose Using DFT Calculation

2016 ◽  
Vol 64 ◽  
pp. 45-62 ◽  
Author(s):  
R. Solaichamy ◽  
J. Karpagam
Keyword(s):  
Charge Transfer ◽  
Density Functional ◽  
Energy Gap ◽  
Chemical Shifts ◽  
Nbo Analysis ◽  
Biological Properties ◽  
Basis Set ◽  
Potential Energy Distribution ◽  
Charge Delocalization ◽  
Ft Raman

In the present study, we report on the Molecular structure and infrared (IR) and FT-Raman studies of Voglibose (VGB) as well as by calculations based on the density functional theory (DFT) approach; utilizing B3LYP/6-31G(d,p) basis set. The targeted interpretation of the vibrational spectra intended to the basis of calculated potential energy distribution matrix (PED) utilizing VEDA4 program. Stability of the molecule arising from hyperconjugative interactions and charge delocalization was studied using natural bond orbital (NBO) analysis. The results show that change in electron density in the σ∗and π∗antibonding orbitals and E2energies confirm the occurrence of intramolecular charge transfer within the molecule. The UV-Visible and NMR spectral analysis were reported by using TD-DFT and gauge GIAO approach respectively and their chemical shifts related to TMS were compared. The lowering of HOMO and LUMO energy gap appears to be the cause for its enhanced charge transfer interactions. Besides, molecular electrostatic potential (MEP) analysis was reported. Due to different potent biological properties, the molecular docking results are also reported.

scholarly journals A Preliminary First Principle Study on Photochromism of Diarylethene Molecules

2019 ◽  
Vol 1 ◽  
pp. 67-77
Author(s):  
Ravi Karki
Keyword(s):  
Molecular Orbital ◽  
Density Functional ◽  
Energy Difference ◽  
Basis Set ◽  
Functional Theory ◽  
Solvation State ◽  
Highest Occupied Molecular Orbital ◽  
Lowest Unoccupied Molecular Orbital ◽  
Energy Consideration ◽  
Hybrid Density Functional

Photochromism in some diarylethene molecules have been studied by using hybrid density functional theory using the ground state energy consideration. In particular, B3LYP functional and all electron basis set 6-311G (2d,2p) as implemented in Gaussian09 suites of program has been used to investigate the energy difference of two stable isomers of stilbene, azobenzene, cyclooctane, and 1,2, dimethylcyclohexane molecules. The energy difference is corroborated to calculate the frequencies of photons that are required to induce photochromism in these molecules in vacuum and in solvation state. The study found that the molecules exhibit photochromism at various frequency range from infra-red to ultraviolet. The binding energy per atom, charge distribution, HOMO-LUMO (Highest Occupied Molecular Orbital and Lowest Unoccupied Molecular Orbital) gap are also calculated for all the molecules in vacuum, water and ethanol solvent. The results obtained are in accordance with the experimental observations.

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