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1.
Int J Vet Sci Med ; 6(2): 286-295, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30564611

RESUMO

Hydroxyapatite is an important biomaterial and main mineral component found in bones for potential clinical applications. Moringa oleifera, a common plant in which all parts are edible and rich in iron content. This study reported the chemically synthesized Hydroxyapatite and green synthesis of Hydroxyapatite nanorods using the aqueous flower extract of Moringa oleifera by microwave assisted method. The synthesized Moringa oleifera flower extract Hydroxyapatite nanorods were characterized by UV-Vis spectroscopy (UV-vis), Fourier Transform Infra Red spectroscopy (FTIR), X-Ray Diffraction analysis (XRD), Transmission Electron Microscopy (TEM), Photo Luminescence spectroscopy (PL), Thermo Gravimetric analysis (TGA) and Energy Dispersive X-ray analysis (EDX). In addition, the antimicrobial activity of these nanorods was assessed. Moringa oleifera flower extract Hydroxyapatite nanorods were crystalline in nature, rod like structure with a mean particle size of 41 nm. The antibacterial activity of Moringa oleifera flower extract capped Hydroxyapatite nanorods was greater against Gram positive bacteria than Gram negative bacteria. Furthermore, Moringa oleifera extract capped Hydroxyapatite nanorods showed a very good antifungal activity against three common pathogenic fungi including; Candida albicans, Aspergillus fumigatus and Aspergillus niger.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 144: 200-14, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-25756688

RESUMO

Organic crystal of 3,5-dinitrosalicylic acid monohydrate has been grown by slow evaporation method at room temperature, using water as solvent. Quantum chemical calculations of energies, geometric structure and vibrational analysis of the title compound are carried out by DFT method with 6-31+G (d,p) basis set. Both the experimental and theoretical spectra confirm the presence of functional groups. Electric dipole moment, polarizability and the first order hyperpolarizability values have been computed theoretically. The (1)H and (13)C nuclear magnetic resonance (NMR) chemical shifts of the molecule are calculated by the gauge independent atomic orbital (GIAO) method and compared with the experimental results. The calculated HOMO-LUMO energies confirm the charge transfer within the molecule. Thermodynamic properties (heat capacity, entropy and enthalpy) of the title compound are determined.


Assuntos
Modelos Moleculares , Dinâmica não Linear , Fenômenos Ópticos , Salicilatos/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cristalização , Elétrons , Ligação de Hidrogênio , Conformação Molecular , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia de Luz Próxima ao Infravermelho , Eletricidade Estática , Termodinâmica , Vibração , Difração de Raios X
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 139: 521-32, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25579654

RESUMO

In this work, the vibrational spectral analysis is carried out by using Raman and infrared spectroscopy in the range 4000-400 cm(-1) and 4000-50 cm(-1) respectively for N,N-Diphenyl Formamide (DPF) molecule. The optimized molecular structures, vibrational frequencies and corresponding vibrational assignments, nuclear magnetic resonance (NMR) and ultraviolet-visible (UV-VIS) spectra of the title molecule are evaluated using density functional theory (DFT) with standard B3LYP/6-31G(d,p) basis set. The harmonic vibrational frequencies are calculated and the scaled values have been compared with experimental FT-IR and FT-Raman spectra. The observed and calculated frequencies are found to be in good agreement. The stability of the molecule arising from hyper conjugative interactions and the charge delocalization has been analyzed using natural bond (NBO) analysis. The possible electronic transitions are determined by HOMO-LUMO orbital shapes and their energies. Thermodynamic properties (heat capacity, entropy and enthalpy) and the first hyperpolarizability of the title compound are calculated. The Mulliken charges and electric dipole moment of the molecule are computed using DFT calculations. The (1)H and (13)C nuclear magnetic resonance (NMR) chemical shift of the molecules are calculated by the gauge independent atomic orbital (GIAO) method and compared with experimental results.


Assuntos
Elétrons , Formamidas/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Vibração , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Entropia , Conformação Molecular , Dinâmica não Linear , Fenômenos Ópticos , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Temperatura
4.
Artigo em Inglês | MEDLINE | ID: mdl-25262142

RESUMO

In this work, the vibrational characteristics of 2-Benzylpyridine have been investigated. The structure of the molecule has been optimized and the structural characteristics of the molecule have been determined by density functional theory B3LYP method with 6-31G(d,p) basis set. The infrared and Raman spectra have been simulated from calculated intensities. Both the experimental and theoretical vibrational data confirms the presence of functional groups in the title compound. The (1)H and (13)C NMR spectra were recorded and (1)H and (13)C nuclear magnetic resonance chemical shifts of the molecule were calculated using the gauge independent atomic orbital method. UV-Visible spectrum of the title compound was recorded in the region 190-1100 nm and the electronic properties HOMO and LUMO energies were calculated by CIS approach. Nonlinear optical and thermodynamic properties were interpreted. All the calculated results were compared with the available experimental data of the title molecule.


Assuntos
Compostos de Benzil/química , Espectroscopia de Ressonância Magnética , Piridinas/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Dimetil Sulfóxido/química , Elétrons , Metilação , Conformação Molecular , Distribuição Normal , Óptica e Fotônica , Teoria Quântica , Solventes/química , Termodinâmica , Ureia/química , Vibração
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 125: 201-10, 2014 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-24556128

RESUMO

This work deals with the vibrational spectra of 2,3,4,5,6-Penta Bromo Toluene (PBT) and Bromo Durene (BD) by quantum chemical calculations. The solid phase FTIR and FT-Raman spectra of the title compounds were recorded in the regions 4000-400 cm(-1) and 4000-50 cm(-1), respectively. The spectra were interpreted with the aid of normal coordinate analysis based on density functional theory (DFT) using B3LYP/6-31G* level and basis set combinations and was scaled using various scale factors yielding a good agreement between observed and calculated frequencies. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of the simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes. The HOMO and LUMO energies were calculated within the molecule. (13)C and (1)H NMR chemical shifts results were also calculated and compared with the experimental values. Thermodynamical properties like entropy heat capacity, zero point energy have been calculated for the title molecules.


Assuntos
Derivados de Benzeno/química , Hidrocarbonetos Bromados/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Tolueno/análogos & derivados , Vibração , Análise de Fourier , Modelos Lineares , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Tolueno/química
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 118: 663-71, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24096062

RESUMO

The vibrational spectra of 5-nitroindan (NI) was computed using B3LYP methodology with 6-31G(*) and 6-31G(**) basis sets. The FTIR and FT-Raman spectra were recorded in the region 4000-400 cm(-1) and 4000-50 cm(-1) respectively. A similarity was achieved between the observed and calculated frequencies by refinement of the scale factors. The (1)H and (13)CNMR chemical shifts results were also compared with the experimental values. The Mulliken charges, the values of electric dipole moment (µ) of the molecule were computed using DFT calculations. The first order hyperpolarizability (ß0) and related properties (ß, α0, and Δα) of both are calculated using B3LYP method on the finite-field approach. The electronic properties HOMO and LUMO energies are calculated. Thermodynamic properties (heat capacity, entropy and enthalpy) of the title compound were calculated.


Assuntos
Indanos/química , Nitrocompostos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Termodinâmica
7.
Artigo em Inglês | MEDLINE | ID: mdl-24247097

RESUMO

Maltol (3-hydroxy-2-methyl-4pyrone) is widely known as metal ions chelator with many practical applications in catalysis, medicine and food chemistry. The FTIR and FT-Raman spectra of maltol have been recorded in the region 4000-400 and 4000-50 cm(-1), respectively. The conformational analysis, optimized geometry, frequency and intensity of the vibrational bands of maltol were obtained by the density functional theory (DFT) with complete relaxation in the potential energy surface using 6-31G* basis set. The observed and the calculated frequencies are found to be in good agreement. The (1)H and (13)C NMR spectra have been recorded and (1)H and (13)C nuclear magnetic resonance chemical shifts of the molecule were also calculated using the gauge independent atomic orbital (GIAO) method and their respective linear correlations were obtained. The electronic properties HOMO and LUMO energies were measured. Thermodynamic properties (heat capacity, entropy and enthalpy) of the title compound were calculated. The Mulliken charges, the values of electric dipole moment (µ) of the molecule were computed using DFT calculations. The first order hyperpolarizability (ßo) and related properties (ß, αo and Δα) of both are calculated using B3LYP/6-31G* method on the finite-field approach. The calculated first hyperpolarizability shows that the molecules are an attractive molecule for future applications in non-linear optics. The intramolecular contacts have been interpreted using Natural Bond Orbital (NBO).


Assuntos
Modelos Moleculares , Dinâmica não Linear , Pironas/química , Teoria Quântica , Elétrons , Modelos Lineares , Espectroscopia de Ressonância Magnética , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Termodinâmica , Vibração
8.
Artigo em Inglês | MEDLINE | ID: mdl-23728077

RESUMO

In the present work, we reported a combined experimental and theoretical study on molecular structure and vibrational analysis of 2,6-dichlorotoluene (DCT) and 2-chloro-6-fluorotoluene (CFT). FTIR and FT-Raman spectra of the title compounds in the solid phase are recorded in the region 4000-400 cm(-1) and 4000-50 cm(-1) respectively. The structural and spectroscopic data of the molecules in the ground state is calculated using Hartree-Fock (HF) and density functional methods (B3LYP) with 3-21 and 6-31G* basis sets. The DFT (B3LYP/31G*) calculations have been giving energies, optimized structures, harmonic vibrational frequencies, IR intensities and Raman activities. The study is extended to the HOMO-LUMO analysis to calculate the energy gap, ionization potential, electron affinity, global hardness, chemical potential and thermodynamic properties of DCT and CFT. A complete vibrational assignment aided by the theoretical harmonic frequency analysis has been proposed. The calculated HOMO and LUMO energies show the charge transfer occurs in the molecule. The harmonic vibrational frequencies have been compared experimental FTIR and FT-Raman spectra. The observed and calculated frequencies are found to be in good agreement. The complete vibrational assignments are performed on the basis of the Total Energy Distribution (TED) of the vibrational modes calculated with scaled quantum mechanical (SQM) method. (13)C NMR chemical shifts results are compared with the experimental values. The experimental spectra also coincide satisfactorily with those of theoretically constructed spectrograms.


Assuntos
Tolueno/análogos & derivados , Halogenação , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Tolueno/química
9.
Artigo em Inglês | MEDLINE | ID: mdl-23266679

RESUMO

This work deals with the vibrational spectra of 2-fluoro 5-nitrotoluene and 2-bromo 5-nitrotoluene by quantum chemical calculations. The solid phase FTIR and FT-Raman spectra of the title compounds were recorded in the regions 4000-400 cm(-1) and 4000-50 cm(-1) respectively. The spectra were interpreted with the aid of normal co-ordinate analysis based on density functional theory (DFT) using standard B3LYP/6-31G(*) basis set for the most optimized geometry. The vibrational frequencies are calculated and scaled values are compared with experimental FTIR and FT-Raman spectra. The scaled theoretical wave numbers showed very good agreement with the experimental ones. The complete vibrational assignments are performed on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. (13)C and (1)H NMR chemical shifts results are compared with the experimental values.


Assuntos
Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Tolueno/análogos & derivados , Tolueno/química , Vibração , Simulação por Computador , Cinética , Modelos Lineares , Espectroscopia de Ressonância Magnética , Conformação Molecular , Dinâmica não Linear , Fenômenos Ópticos , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
10.
Artigo em Inglês | MEDLINE | ID: mdl-22750683

RESUMO

In this work, the experimental and theoretical vibrational spectra of 6-chloro-o-cresol (COC) and 4-chloro-3-methylphenol (CMP) have been studied. FTIR and FT-Raman spectra of the title compounds in the solid phase are recorded in the region 4000-400 cm(-1) and 4000-50 cm(-1), respectively. The structural and spectroscopic data of the molecules in the ground state are calculated by using density functional methods (B3LYP) with 6-31G basis set combinations. The calculated vibrational frequencies are scaled by normal coordinate analysis based on a scaled quantum mechanical force field. The obtained values are compared with experimental FTIR and FT-Raman spectra. The observed and calculated frequencies are found to be in good agreement. The complete vibrational assignments are performed on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The results of (13)C and (1)H NMR chemical shift are compared with the experimental values.


Assuntos
Cresóis/química , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Simulação por Computador , Modelos Lineares , Espectroscopia de Ressonância Magnética , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Vibração
11.
Artigo em Inglês | MEDLINE | ID: mdl-22343112

RESUMO

The solid phase FTIR and FT-Raman spectra of 2-chloro-4-nitrotoluene (2Cl4NT) and 4-chloro-2-nitrotoluene (4Cl2NT) were recorded in the regions 4000-400 cm(-1) and 4000-50 cm(-1) respectively. The fundamental vibrational frequencies and intensities of the vibrational bands were evaluated using density functional theory (DFT) with B3LYP method and standard 6-31G* basis set combinations. The infrared and Raman spectra were also predicted from the calculated intensities. The vibrational spectra were interpreted with the aid of normal coordinate analysis based on a scaled quantum mechanical force field. The calculated HOMO and LUMO energies showed that charge transfer had occurred within the molecule. Comparison of simulated spectra with the experimental spectra provided important information about the ability of the computational method to describe the vibrational modes. (13)C NMR chemical shifts results were also compared with the experimental values.


Assuntos
Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Tolueno/análogos & derivados , Halogenação , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Tolueno/química
12.
Artigo em Inglês | MEDLINE | ID: mdl-22104327

RESUMO

The vibrational spectra of 1,2-dichloro-4-nitrobenzene (DCNB) and 2,3,5,6-tetrachloro-1-nitrobenzene (TCNB) were computed using B3LYP methodology with 6-31G* basis set. The solid phase FTIR and FT-Raman spectra were recorded in the region 4000-400 cm(-1) and 4000-50 cm(-1), respectively. A similarity was achieved between the observed and calculated frequencies by refinement of the scale factors. The HOMO and LUMO energies were calculated. (13)C and (1)H NMR chemical shifts results were also compared with the experimental values.


Assuntos
Modelos Moleculares , Nitrobenzenos/química , Teoria Quântica , Vibração , Absorção , Simulação por Computador , Cinética , Modelos Lineares , Espectroscopia de Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Termodinâmica
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 79(5): 1959-68, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21703911

RESUMO

In this work, the experimental and theoretical vibrational spectra of pyrazole (PZ) and 3,5-dimethyl pyrazole (DMP) have been studied. FTIR and FT-Raman spectra of the title compounds in the solid phase are recorded in the region 4000-400 cm(-1) and 4000-50 cm(-1), respectively. The structural and spectroscopic data of the molecules in the ground state are calculated using density functional methods (B3LYP) with 6-311+G** basis set. The vibrational frequencies are calculated and scaled values are compared with experimental FTIR and FT-Raman spectra. The observed and calculated frequencies are found to be in good agreement. The complete vibrational assignments are performed on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SM) method. 13C and 1H NMR chemical shifts results are compared with the experimental values.


Assuntos
Pirazóis/química , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Espectroscopia de Ressonância Magnética , Modelos Químicos , Estrutura Molecular , Vibração
14.
Artigo em Inglês | MEDLINE | ID: mdl-17804282

RESUMO

This work deals with the vibrational spectroscopy of 1-naphthyl acetic acid. The molecular vibrations of 1-naphthyl acetic acid (NAA) is investigated in polycrystalline sample, at room temperature, by Fourier transform infrared (FT-IR) and FT-Raman spectroscopy. In parallel, ab initio and various density functional (DFT) methods were used to determine the geometrical, energetic and vibrational characteristics of NAA. On the basis of B3LYP/6-311+G** method and basis set combinations, a normal mode analysis was performed to assign the various fundamental frequencies according to the total energy distribution (TED). Simulation of infrared and Raman spectra, utilizing the results of these calculations led to excellent overall agreement with observed spectral patterns by refinement of scale factors.


Assuntos
Ácidos Naftalenoacéticos/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Vibração , Carbono/química , Simulação por Computador , Estrutura Molecular , Ácidos Naftalenoacéticos/química , Temperatura
15.
Artigo em Inglês | MEDLINE | ID: mdl-17822949

RESUMO

The solid phase mid FTIR and FT Raman spectra of 2-naphthoic acid (NA) and 6-bromo-2-naphthoic acid (BNA) have been recorded in the regions 4000-400 cm(-1) and 3500-100 cm(-1), respectively. The fundamental vibrational frequencies and intensities of the vibrational bands were evaluated using density functional theory (DFT) using standard B3LYP method and 6-311+G** basis set combinations. The vibrational spectra were interpreted, with the aid of normal coordinate analysis based on a scaled quantum mechanical force field. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes.


Assuntos
Bromo/química , Naftalenos/química , Vibração , Biologia Computacional/métodos , Modelos Moleculares , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos
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