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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(6): 1998-2000, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30053367

RESUMO

In this Study, Cadmium Oxide (CdO) nanostructures were synthesized by using Chemical Bath Deposition Technique. The synthesized process was carried out at room temperature. The structural and optical properties of nanostructures was characterized by XRD, SEM and UV-Vis techniques. As a result, the CdO nanostructures are oriented along (111) plane of cubic crystal structure. The morphology of CdO nanostructures showed interconnected prism-like and cauliflower-type cluster nanostructure. The UV results of this structures with high absorbtion coefficient are observed to be in accordance with the CdO nanoparticles.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 142: 169-77, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25703361

RESUMO

In this study, theoretical harmonic vibrational frequencies and geometric parameters of N-(4-methoxybenzoyl)-2-methylbenzenesulfonamide have been investigated by Hartree-Fock (HF), density functional theory (B3LYP hybrid functional) methods with 6-311++G (d,p) basis set, for the first time. Experimental FT-IR (400-4000cm(-1)) and Laser-Raman spectra (100-4000cm(-1)) of title compound in solid phase have been recorded. Interaction energies, N-H⋯O hydrogen bonds, C-H⋯O and aromatic π⋯π stacking interactions in dimer structures of the title compound have been evaluated by the calculation methods. The dimer calculations have aimed to present the efficacy and performance of M06-2X hybrid functional on the intermolecular interactions and more strongly bound systems for the corrected and interaction energy by the counterpoise correction procedure. The interaction energies by M06-2X approach give more stable results than HF and B3LYP, extremely. The more strongly bonds, especially, on N-H⋯O hydrogen bonds and π⋯π interaction for the both dimer structure have also supported that the M06-2X functional of density functional is more effective.


Assuntos
Derivados de Benzeno/química , Sulfonamidas/química , Dimerização , Ligação de Hidrogênio , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 137-46, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25062059

RESUMO

In present study, the experimental and theoretical harmonic vibrational frequencies of gliclazide molecule have been investigated. The experimental FT-IR (400-4000 cm(-1)) and Laser-Raman spectra (100-4000 cm(-1)) of the molecule in the solid phase were recorded. Theoretical vibrational frequencies and geometric parameters (bond lengths and bond angles) have been calculated using ab initio Hartree Fock (HF), density functional theory (B3LYP hybrid function) methods with 6-311++G(d,p) and 6-31G(d,p) basis sets by Gaussian 09W program. The assignments of the vibrational frequencies were performed by potential energy distribution (PED) analysis by using VEDA 4 program. Theoretical optimized geometric parameters and vibrational frequencies have been compared with the corresponding experimental data, and they have been shown to be in a good agreement with each other. Also, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies have been found.


Assuntos
Gliclazida/química , Hipoglicemiantes/química , Modelos Moleculares , Teoria Quântica , Vibração , Elétrons , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Termodinâmica
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 126: 280-90, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24608012

RESUMO

In this study, the experimental and theoretical vibrational frequencies of a newly synthesized potential anti-inflammatory agent namely, 4-benzyl-3-(thiophen-2-yl)-4,5-dihydro-1H-1,2,4-triazole-5-thione have been investigated. The experimental FT-IR (4000-400cm(-1)) and Laser-Raman spectra (4000-100cm(-1)) of the molecule in solid phase have been recorded. The theoretical vibrational frequencies and the optimized geometric parameters (bond lengths, bond angles and dihedral angles) have been calculated using density functional theory methods (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr and DFT/M06-2X: the highly parameterized, empirical exchange correlation function) with 6-311++G(d,p) basis set by Gaussian 09W software, for the first time. The assignments of the vibrational frequencies have been done by potential energy distribution (PED) analysis using VEDA 4 software program. The theoretical optimized geometric parameters and vibrational frequencies have been found to be in good agreement with the corresponding experimental data and results in the literature. In addition, the highest occupied molecular orbital (HOMO) energy, the lowest unoccupied molecular orbital (LUMO) energy and the other related molecular energy values of the compound have been investigated using the same theoretical calculations.


Assuntos
Tionas/química , Triazóis/química , Modelos Moleculares , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Tiofenos/química
5.
Artigo em Inglês | MEDLINE | ID: mdl-24589995

RESUMO

In this study, the experimental and theoretical vibrational frequencies of a newly synthesized potential chemotherapeutic agent namely, 2-[(2-methoxyl)sulfanyl]-4-(2-methylpropyl)-6-oxo-1,6-dihydropyrimidine-5-carbonitrile have been investigated. The experimental FT-IR (4000-400cm(-1)) and Laser-Raman spectra (4000-100cm(-1)) of the molecule in solid phase have been recorded. The theoretical vibrational frequencies and optimized geometric parameters (bond lengths and bond angles) have been calculated by using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr) and M06-2X (the highly parametrized, empirical exchange correlation function) quantum chemical methods with 6-311++G(d,p) basis set by Gaussian 09W software, for the first time. The assignments of the vibrational frequencies have been done by potential energy distribution (PED) analysis by using VEDA 4 software. The theoretical optimized geometric parameters and vibrational frequencies have been found to be in good agreement with the corresponding experimental data, and with the results in the literature. In addition, the highest occupied molecular orbital (HOMO) energy, the lowest unoccupied molecular orbital (LUMO) energy and the other related molecular energy values of the compound have been investigated using the same theoretical calculations.


Assuntos
Nitrilas/química , Pirimidinas/química , Cristalografia por Raios X , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
6.
Artigo em Inglês | MEDLINE | ID: mdl-24632154

RESUMO

In the present work, the experimental and theoretical vibrational spectra of 5-hydroxymethyluracil were investigated. The FT-IR (4000-400cm(-1)) spectrum of the molecule in the solid phase was recorded. The geometric parameters (bond lengths and bond angles), vibrational frequencies, Infrared intensities of the title molecule in the ground state were calculated using density functional B3LYP and M06-2X methods with the 6-311++G(d,p) basis set for the first time. The optimized geometric parameters and theoretical vibrational frequencies were found to be in good agreement with the corresponding experimental data, and with the results found in the literature. The vibrational frequencies were assigned based on the potential energy distribution using the VEDA 4 program. The dimeric form of 5-hydroxymethyluracil molecule was also simulated to evaluate the effect of intermolecular hydrogen bonding on its vibrational frequencies. It was observed that the NH stretching modes shifted to lower frequencies, while its in-plane and out-of-plane bending modes shifted to higher frequencies due to the intermolecular NH⋯O hydrogen bond. Also, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies and diagrams were presented.


Assuntos
Simulação por Computador , Modelos Químicos , Simulação de Dinâmica Molecular , Pentoxil (Uracila)/análogos & derivados , Ligação de Hidrogênio , Pentoxil (Uracila)/química , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Artigo em Inglês | MEDLINE | ID: mdl-24662757

RESUMO

In this study, the experimental and theoretical vibrational spectral analysis of 4-(3-fluorophenyl)-1-(propan-2-ylidene)-thiosemicarbazone have been carried out. The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) have been recorded for the solid state samples. The theoretical vibrational frequencies and the optimized geometric parameters (bond lengths and angles) have been calculated for gas phase using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr) and M06-2X (the highly parametrized, empirical exchange correlation function) quantum chemical methods with 6-311++G(d,p) basis set. The diversity in molecular geometry of fluorophenyl substituted thiosemicarbazones has been discussed based on the X-ray crystal structure reports and theoretical calculation results from the literature. The assignments of the vibrational frequencies have been done on the basis of potential energy distribution (PED) analysis by using VEDA4 software. A good correlation was found between the computed and experimental geometric and vibrational data. In addition, the highest occupied (HOMO) and lowest unoccupied (LUMO) molecular orbital energy levels and other related molecular energy values of the compound have been determined using the same level of theoretical calculations.


Assuntos
Hidrocarbonetos Fluorados/química , Modelos Moleculares , Software , Tiossemicarbazonas/química , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 128: 109-18, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24662759

RESUMO

In this study, the experimental and theoretical vibrational frequencies of a newly synthesized bioactive agent namely, 2-Trifluoromethyl-10H-benzo[4,5]-imidazo[1,2-a]pyrimidin-4-one (TIP) have been investigated. The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) of the molecule in solid phase have been recorded. The theoretical vibrational frequencies and the optimized geometric parameters (bond lengths and bond angles) have been calculated using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr) and M06-2X (the highly parametrized, empirical exchange correlation function) quantum chemical methods with 6-311++G(d,p) basis set by Gaussian 09W software, for the first time. The assignments of the vibrational frequencies have been done by potential energy distribution (PED) analysis using VEDA 4 software. The theoretical optimized geometric parameters and vibrational frequencies have been found to be in good agreement with the corresponding experimental data and results in the literature. In addition, the highest occupied molecular orbital (HOMO) energy, the lowest unoccupied molecular orbital (LUMO) energy and the other related molecular energy values of the compound have been investigated using the same theoretical calculations.


Assuntos
Compostos Heterocíclicos com 3 Anéis/química , Modelos Moleculares , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 128: 119-26, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24662760

RESUMO

In this study, the experimental and theoretical vibrational frequencies of a newly synthesized 2,3,4,5,6-Pentafluoro-trans-cinnamic acid have been investigated. The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) of the molecule in solid phase have been recorded. The theoretical vibrational frequencies and optimized geometric parameters (bond lengths and bond angles) have been calculated by using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr) and DFT/M06-2X (the highly parameterized, empirical exchange correlation function) quantum chemical methods with 6-311++G(d,p) basis set by Gaussian 09W software, for the first time. The assignments of the vibrational frequencies have been done by potential energy distribution (PED) analysis by using VEDA 4 software. The theoretical optimized geometric parameters and vibrational frequencies have been found to be in good agreement with the corresponding experimental data, and with the results in the literature. In addition, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energies and the other related molecular energy values have been calculated and depicted.


Assuntos
Cinamatos/química , Hidrocarbonetos Fluorados/química , Modelos Moleculares , Cinamatos/síntese química , Hidrocarbonetos Fluorados/síntese química , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 118: 816-27, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24152866

RESUMO

We have synthesized ethyl (2E)-3-amino-2-({[(4-benzoyl-1,5-diphenyl-1H-pyrazol-3-yl)carbonyl]amino}carbonothioyl)but-2-enoate (2) by the reaction of 4-benzoyl-1,5-diphenyl-1H-pyrazole-3-carbonyl chloride (1), ammonium thiocyanate and ethyl 3-aminobut-2-enoate and then characterized by elemental analyses, IR, Raman, (1)H NMR, (13)C NMR and X-ray diffraction methods. The experimental and theoretical vibrational spectra of 2 were investigated. The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) of the molecule in the solid phase were recorded. Theoretical vibrational frequencies and geometric parameters (bond lengths, bond angles) were calculated using Ab Initio Hartree Fock (HF), Density Functional Theory (B3LYP) methods with 6-311++G(d,p) basis set by Gaussian 09W program. The computed values of frequencies are scaled using a suitable scale factor to yield good coherence with the observed values. The assignments of the vibrational frequencies were performed by potential energy distribution (PED) analysis by using VEDA 4 program. The theoretical optimized geometric parameters and vibrational frequencies were compared with the corresponding experimental X-ray diffraction data, and they were seen to be in a good agreement with each other. Also, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energies were calculated.


Assuntos
Amidas/química , Pirazóis/química , Compostos de Bifenilo/química , Butanóis/química , Cristalografia por Raios X , Modelos Moleculares , Análise Espectral
11.
Artigo em Inglês | MEDLINE | ID: mdl-24177876

RESUMO

In this study, the experimental and theoretical vibrational frequencies of a newly synthesized potential chemotherapeutic agent namely, 6-(2-methylpropyl)-4-oxo-2-sulfanylidene-1,2,3,4-tetrahydropyrimidine-5-carbonitrile have been investigated. The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) of the molecule in solid phase have been recorded. The theoretical vibrational frequencies and optimized geometric parameters (bond lengths and bond angles) have been calculated by using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr) and M06-2X (the highly parametrized, empirical exchange correlation function) quantum chemical methods with 6-311++G(d,p) basis set by Gaussian 09 W software, for the first time. The assignments of the vibrational frequencies have been done by potential energy distribution (PED) analysis by using VEDA 4 software. The theoretical optimized geometric parameters and vibrational frequencies have been found to be in good agreement with the corresponding experimental data, and with the results in the literature. In addition, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energies and the other related molecular energy values have been calculated and depicted.


Assuntos
Nitrilas/química , Pirimidinas/química , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
12.
Artigo em Inglês | MEDLINE | ID: mdl-23714189

RESUMO

In the present work, the experimental and theoretical vibrational spectra of 4-chlorobenzothioamide were investigated. The FT-IR (400-4000 cm(-1)) and µ-Raman spectra (100-4000 cm(-1)) of 4-chlorobenzothioamide in the solid phase were recorded. The geometric parameters (bond lengths and bond angles), vibrational frequencies, Infrared and Raman intensities of the title molecule in the ground state were calculated using ab initio Hartree-Fock and density functional theory (B3LYP) methods with the 6-311++G(d,p) basis set for the first time. The optimized geometric parameters and the theoretical vibrational frequencies were found to be in good agreement with the corresponding experimental data and with the results found in the literature. The vibrational frequencies were assigned based on the potential energy distribution using the VEDA 4 program. The dimeric form of 4-chlorobenzothioamide was also simulated to evaluate the effect of intermolecular hydrogen bonding on the vibrational frequencies. It was observed that the N-H stretching modes shifted to lower frequencies, while the in-plane and out-of-plane bending modes shifted to higher frequencies due to the intermolecular N-H···S hydrogen bond. Also, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies and diagrams were presented.


Assuntos
Amidas/química , Análise Espectral Raman , Tioamidas/química , Vibração , Ligação de Hidrogênio , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 107: 248-55, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23434551

RESUMO

In the present study, the experimental and theoretical harmonic and anharmonic vibrational frequencies of 4-chloro-3-nitrobenzonitrile were investigated. The experimental FT-IR (400-4000 cm(-1)) and µ-Raman spectra (100-4000 cm(-1)) of the molecule in the solid phase were recorded. Theoretical vibrational frequencies and geometric parameters (bond lengths and bond angles) were calculated using ab initio Hartree Fock (HF), density functional B3LYP and M06-2X methods with 6-311++G(d,p) basis set by Gaussian 09 W program, for the first time. The assignments of the vibrational frequencies were performed by potential energy distribution (PED) analysis by using VEDA 4 program. The theoretical optimized geometric parameters and vibrational frequencies were compared with the corresponding experimental data, and they were seen to be in a good agreement with each other. Also, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies were found.


Assuntos
Nitrilas/química , Nitrobenzenos/química , Halogenação , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
14.
J Mol Model ; 18(9): 4453-64, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22643971

RESUMO

In the present work, the experimental and the theoretical vibrational spectra of trifluorothymine were investigated. The FT-IR (400-4000 cm(-1)) and µ-Raman spectra (100-4000 cm(-1)) of trifluorothymine in the solid phase were recorded. The geometric parameters (bond lengths and bond angles) and vibrational frequencies of the title molecule in the ground state were calculated using ab initio Hartree-Fock (HF) method and density functional theory (B3LYP) method with the 6-31++G(d,p) and 6-311++G(d,p) basis sets for the first time. The optimized geometric parameters and the theoretical vibrational frequencies were found to be in good agreement with the corresponding experimental data and with results found in the literature. Vibrational frequencies were assigned based on the potential energy distribution using the VEDA 4 program. The dimeric form of trifluorothymine was also simulated to evaluate the effect of intermolecular hydrogen bonding on the vibrational frequencies. It was observed that the stretching modes shifted to lower frequencies, while the in-plane and out-of-plane bending modes shifted to higher frequencies due to the intermolecular N-H⋯O hydrogen bonds.


Assuntos
Antineoplásicos/química , Antivirais/química , Análise Espectral Raman , Timina/química , Vibração , Dimerização , Ligação de Hidrogênio , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
15.
Artigo em Inglês | MEDLINE | ID: mdl-22459894

RESUMO

In the present study, the experimental and theoretical vibrational spectra of 5-bromo-2'-deoxyuridine were investigated. The experimental FT-IR (400-4000 cm(-1)) and µ-Raman spectra (100-4000 cm(-1)) of the molecule in the solid phase were recorded. Theoretical vibrational frequencies and geometric parameters (bond lengths and bond angles) were calculated using ab initio Hartree Fock (HF) and density functional B3LYP method with 6-31G(d), 6-31G(d,p), 6-311++G(d) and 6-311++G(d,p) basis sets by Gaussian program, for the first time. The assignments of vibrational frequencies were performed by potential energy distribution by using VEDA 4 program. The optimized geometric parameters and theoretical vibrational frequencies are compared with the corresponding experimental data and they were seen to be in a good agreement with the each other. Also, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies were found.


Assuntos
Bromodesoxiuridina/química , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
16.
Artigo em Inglês | MEDLINE | ID: mdl-21530380

RESUMO

Experimental and theoretical vibrational spectra of ß-2-aminopyridinium dihydrogenphosphate (ß-2APDP) have been investigated. The FT-IR spectrum of ß-2APDP was recorded in the region 4000-400 cm(-1). The optimized molecular structure and theoretical vibrational frequencies of ß-2APDP have been investigated using ab initio Hartree-Fock (HF) and density functional B3LYP method with 6-311++G(d,p) basis set. The optimized geometric parameters (bond lengths and bond angles) and theoretical frequencies have been compared with the corresponding experimental data and it is found that they agree well with each other. All the assignments of the theoretical frequencies were performed by potential energy distributions using VEDA 4 program. Furthermore, the used scale factors were obtained from the ratio of the frequency values of the strongest peaks in the experimental and theoretical IR spectra. From the results it was concluded that the B3LYP method is superior to the HF method for the vibrational frequencies.


Assuntos
Concentração de Íons de Hidrogênio , Compostos de Piridínio/química , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier
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