The spectroscopic NMR analysis of 2-dicyanovinyl-5-phenylthiophene by the density functional method

2013 ◽  
Vol 91 (6) ◽  
pp. 375-381 ◽  
Author(s):  
Xiao-Hong Li ◽  
Xian-Zhou Zhang
Keyword(s):  
Title Compound ◽  
Density Functional ◽  
Density Functional Method ◽  
Functional Method ◽  
Energy Distributions ◽  
Compound A ◽  
H Nmr ◽  
Quantum Chemistry Calculations ◽  
Detailed Interpretation ◽  
Calculated Potential Energy

Quantum chemistry calculations have been performed by using the Gaussian03 program to compute the optimized geometry and harmonic vibrational frequency of 2-dicyanovinyl-5-phenylthiophene (C14H8N2S) in the ground state. Atomic charges at B3LYP/6-311++G(d,p) level are also calculated. Potential energy distributions (PEDs) using MOLVIB program are also used to interpret the theoretical vibrational spectra of the title compound. A detailed interpretation of the infrared spectra of the title compound is reported. The theoretical spectrograms for the IR spectra of the title compound have been constructed. The crystal structure obtained by molecular mechanics belongs to the P21 space group, with lattice parameters Z = 2, a = 6.6745 Å, b = 14.7672 Å, c = 11.0986 Å, ρ = 0.921 g cm–3. In addition, the 13C and 1H NMR are further investigated by the B3LYP/6-311++G(d,p) and B3LYP/6-311++G(2d,2p) methods.

scholarly journals Density functional theory study on the molecular structure of loganin

2011 ◽  
Vol 25 (6) ◽  
pp. 287-302 ◽  
Author(s):  
Anoop Kumar Pandey ◽  
Shamoon Ahmad Siddiqui ◽  
Apoorva Dwivedi ◽  
Kanwal Raj ◽  
Neeraj Misra
Keyword(s):  
Molecular Structure ◽  
Density Functional ◽  
Solid Phase ◽  
Density Functional Method ◽  
Functional Method ◽  
Basis Set ◽  
Equilibrium Geometry ◽  
B3lyp Method ◽  
Ft Ir ◽  
Detailed Interpretation

The computational Quantum Chemistry (QC) has been used for different types of problems, for example: structural biology, surface phenomena and liquid phase. In this paper we have employed the density functional method for the study of molecular structure of loganin. The equilibrium geometry, harmonic vibrational frequencies and infrared intensities were calculated by B3LYP/6-311G (d, p) method and basis set combinations. It was found that the optimized parameters obtained by the DFT/B3LYP method are very near to the experimental ones. A detailed conformational analysis was carried out. A detailed interpretation of the infrared spectra of loganin is also reported in the present work. The FT-IR spectra of loganin were recorded in solid phase. The thermodynamic calculations related to the title compound were also performed at B3LYP/6-311G (d, p) level of theory.

Vibrational Study and Electronic Parameters of "2-Diphenylphosphanyl- 6-fluoro-pyridine"using First Principle

2017 ◽  
Vol 9 (02) ◽  
pp. 125-130
Author(s):  
Tanveer Hasan ◽  
P. K. Singh ◽  
S. H. Mehdi
Keyword(s):  
Title Compound ◽  
Quantum Chemical ◽  
Density Functional ◽  
Density Functional Method ◽  
Vibrational Analysis ◽  
Functional Method ◽  
Orbital Energy ◽  
Electronic Parameters ◽  
Chemical Studies ◽  
Equilibrium Geometries

Vibrational investigations along with theoretical quantum chemical studies on “2-Diphenylphosphanyl-6-fluoro-pyridine (C17H14NFP)” have been carried out. The quantum chemical density functional method at B3LYP/3-21Glevel is used to obtain the equilibrium geometries of the title compound. We have also performed vibrational analysis of the title compound at their equilibrium geometries and established the complete assignments of the significant vibrational modes. Electronic parameters such as HOMO, LUMO and frontier orbital energy band gap, has been calculated. Besides it the thermodynamical parameters like internal thermal energy, entropy and constant volume specific heat capacity have been calculated.

A THEORETICAL INVESTIGATION OF THE INTERACTIONS BETWEEN CELLULOSE AND 1-BUTYL-3-METHYLIMIDAZOLIUM CHLORIDE

2010 ◽  
Vol 09 (03) ◽  
pp. 611-624 ◽  
Author(s):  
JINXIN GUO ◽  
DONGJU ZHANG ◽  
CHENGBU LIU
Keyword(s):  
Hydrogen Bonds ◽  
Density Functional ◽  
Density Functional Method ◽  
Functional Method ◽  
Chloride Anion ◽  
Cellulose Dissolution ◽  
Hydrogen Atoms ◽  
Imidazolium Cation ◽  
Quantum Chemistry Calculations ◽  
Weak Hydrogen Bonds

To better understand the interactions between cellulose and imidazolium-based ionic liquids (ILs), quantum chemistry calculations have been performed on the systems composed of one cellulose unit with the anion, cation, and the ion pair of 1-butyl-3-methylimidazolium chloride ( [bmim]Cl ) by the density functional method. The relevant geometries, energies, electronic properties and IR characteristics have been systematically discussed. It is found that H-bond interaction is essential for the systems under consideration. The hydroxyls in cellulose bind to chloride anions strongly through H -bonds, which could be predominant to cellulose dissolution in ILs. Chloride anion prefers to occur between two adjacent hydroxyls in cellulose to form bridging OH⋯Cl⋯HO hydrogen bonds. In contrast, weak hydrogen bonds exist between the hydrogen atoms on the imidazolium cation and hydroxyl oxygen atoms of cellulose, which are too much weaker than the hydrogen bonds between the cellulose hydroxyls and chloride anions to be detected by the experiments. The phenomena of cellulose dissolution in ILs should be a result of the joint interactions of chloride anions and [bmim]+ cations with hydroxyls in cellulose.

Vibrational Investigation of "2-Arsanyl-Pyridine" Using First Principle

2017 ◽  
Vol 9 (01) ◽  
pp. 01-04
Author(s):  
Tanveer Hasan ◽  
P. K. Singh
Keyword(s):  
Title Compound ◽  
Quantum Chemical ◽  
Density Functional ◽  
Density Functional Method ◽  
Vibrational Analysis ◽  
Functional Method ◽  
Perfect Agreement ◽  
Chemical Studies ◽  
Quantum Chemical Studies ◽  
Equilibrium Geometries

Spectroscopic investigations along with theoretical quantum chemical studies on “2-Arsanyl-Pyridine (C5H7AsN)” have been carried out. The quantum chemical density functional method at B3LYP/6-31+g(d,p) level, is used to obtain the equilibrium geometries of the title compound. We have also performed vibrational analysis of the title compound at their equilibrium geometries and established the complete assignments of the significant vibrational modes. The calculated vibrational frequencies are shown to be in perfect agreement with the theoretically observed FTIR spectra of the molecule under study.

scholarly journals NLO and NBO Analysis of Sarcosine-Maleic Acid by Using HF and B3LYP Calculations

2013 ◽  
Vol 2013 ◽  
pp. 1-16 ◽  
Author(s):  
N. Günay ◽  
H. Pir ◽  
D. Avcı ◽  
Y. Atalay
Keyword(s):  
Molecular Structure ◽  
Maleic Acid ◽  
Title Compound ◽  
Density Functional ◽  
Density Functional Method ◽  
Nbo Analysis ◽  
Functional Method ◽  
Basis Set ◽  
Charge Delocalization ◽  
Hartree Fock

We report a theoretical study on molecular structure, vibrational spectra, nonlinear optical (NLO), and natural bond orbital (NBO) analysis of sarcosine-maleic acid (C7H11NO6) in the ground state calculated by using the Hartree-Fock (HF) and density functional method (DFT/B3LYP) with 6–31++G(d,p) basis set. We repeat NBO calculations with 6–31G(d,p) basis set so as to see the diffuse function impact on NBO analysis. Stability of the molecule arising from hyper conjugative interactions and charge delocalization has been analyzed using NBO analysis. NBO analysis shows that there is a O–H⋯O and N–H⋯O hydrogen bond in the title compound, which is consistent with the conclusion obtained by the analysis of molecular structure. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. Also, these results are supported by the NLO parameters. Finally, the calculated results were applied to simulate infrared and Raman spectra of the title compound which showed good agreement with experimental ones.

Computer Simulation of an Synthetic Ultraviolet Absorbent in the Interface of DMB and DMF

2010 ◽  
Vol 146-147 ◽  
pp. 966-971
Author(s):  
Qi Hua Jiang ◽  
Hai Dong Zhang ◽  
Bin Xiang ◽  
Hai Yun He ◽  
Ping Deng
Keyword(s):  
Computer Simulation ◽  
Computer Simulations ◽  
Density Functional ◽  
Density Functional Method ◽  
Mean Field ◽  
Functional Method ◽  
Dynamic Density ◽  
Interface Phase ◽  
Simulation Results

This work studies the aggregation of an synthetic ultraviolet absorbent, named 2-hydroxy-4-perfluoroheptanoate-benzophenone (HPFHBP), in the interface between two solvents which can not completely dissolve each other. The aggregation is studied by computer simulations based on a dynamic density functional method and mean-field interactions, which are implemented in the MesoDyn module and Blend module of Material Studios. The simulation results show that the synthetic ultraviolet absorbent diffuse to the interface phase and the concentration in the interface phase is greater than it in the solvents phase.

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