The Absorption Energy and Equilibrium Structure Analysis of CH4 on Coal Molecules

2013 ◽  
Vol 807-809 ◽  
pp. 2366-2370
Author(s):  
Hua Ping Yang ◽  
Ming Li ◽  
Zheng Xin Yan ◽  
Dong Zhi Yan
Keyword(s):  
Structure Analysis ◽  
Dft Method ◽  
Equilibrium Structure ◽  
Atomic Charges ◽  
Absorption Model ◽  
Absorption Energy ◽  
Molecule Model ◽  
Basic Sets

The coal molecule model and the absorption model of coal and methane were established according to Van der Walls force. The coal molecule model and the absorption model of coal and methane were optimized and obtained absorption energy and equilibrium structure with the DFT method with 6-311G++ basic sets. The effects of coal molecule on the absorption position, absorption energy and absorption distance of CH4 were presented by analyzing the Mulliken atomic charges of coal molecules.

Analysis of Adsorbed Methane Gas Structure and Mullikan Charges

2014 ◽  
Vol 962-965 ◽  
pp. 1118-1122
Author(s):  
Hua Ping Yang ◽  
Ming Li
Keyword(s):  
Adsorption Process ◽  
Adsorption Equilibrium ◽  
Dft Method ◽  
Model Structure ◽  
Dispersion Forces ◽  
Methane Gas ◽  
Adsorbed Methane ◽  
Molecule Model ◽  
Equilibrium Geometries ◽  
Basic Sets

The methane molecule model, the coal molecule model and the absorption model of coal and methane have been thoroughly investigated using the DFT method,Van der Walls force radius as boundary conditions as well. The investigations focuses on optimizing the three types of model structure. Meanwhile, adsorption equilibrium geometries with 6-311G++ basic sets have been established. Through the model analysis of the changes in the structure and Millikan charge from free state to the adsorption states, the results indicate that the adsorption process of methane gas on the coal in the Van der Walls force mainly dispersion forces and induction force, methane molecules are polarized in the adsorption process, the electric dipole moment.

Molecular structure, Vibrational assignment, HOMO-LUMO and Mulliken analysis of 2-[4-amino-2-(4-methylphenylamino) thiazol-5-oyl]benzothiazole(AMPATOB)

2016 ◽  
Vol 2 (1) ◽  
pp. 38
Author(s):  
Dr A Yardily
Keyword(s):  
Molecular Structure ◽  
Mass Spectra ◽  
Density Functional ◽  
Dft Method ◽  
Dihedral Angles ◽  
Atomic Charges ◽  
Vibrational Assignment ◽  
Functional Theory ◽  
Wave Numbers ◽  
Homo Lumo

The compound 2-[4-amino-2-(4-methylphenylamino) thiazol-5-oyl]benzothiazole (AMPATOB) was prepared from 1-(4-methylphenyl)-3-(N-nitroamidino)thiourea and 2-(2-bromoacetyl)benzothiazole in the presence of triethylamine and characterised  by FTIR, NMR and mass spectra. The geometry of the molecule was investigated and optimized with the help of B3LYP/ 6-31G density functional theory (DFT) method using Gaussian 09 software package.The calculated geometries such as bond lengths, bond angles, dihedral angles, atomic charges, harmonic vibrational wave numbers and intensities of vibrational bonds of the titled compound were investigated. The experimental 1H NMR and IR spectrum was compared with theoretical value. The molecule consists of three ring systems, all are lying in one plane.

AB INITIO STUDY OF SPECTROSCOPIC CONSTANTS AND ANHARMONIC FORCE FIELD OF AsH2 RADICAL

2011 ◽  
Vol 10 (06) ◽  
pp. 849-860 ◽  
Author(s):  
YURONG GUO ◽  
MEISHAN WANG ◽  
CHUANLU YANG ◽  
YUTING SUN ◽  
ZILIANG ZHU
Keyword(s):  
Force Field ◽  
Experimental Studies ◽  
Dft Method ◽  
Equilibrium Structure ◽  
Vibrational Frequencies ◽  
Force Constants ◽  
Basis Sets ◽  
Spectroscopic Constants ◽  
Rotational Constants ◽  
Anharmonic Force

The equilibrium structure, spectroscopic constants and anharmonic force field of AsH2 have been investigated at B3LYP, B3PW91 and MP2 methods employing the basis sets of cc-pVNZ and aug-cc-pVNZ (N ∈ { T , Q }), respectively. The computed geometries, rotational constants, part of vibrational frequencies, quartic and sextic centrifugal distortion constants are compared with the available experimental data or theoretical results. The other vibrational frequencies, equilibrium rotational constants, anharmonic constants, vibration–rotation interaction constants, cubic and quartic force constants of AsH2 are also predicted for the first time. Furthermore, the calculated results show that the DFT method is superior to MP2 at the calculations of geometries, spectroscopic constants and force constants. The B3PW91/aug-cc-pVQZ results are more reliable. Our predictions can provide useful data for the experimental studies of the corresponding spectroscopic constants of AsH2 .

scholarly journals Comparison of the Stability of 2H Nanosurfaces by the Adsorption of Small Molecules : A DFT Study

2021 ◽  
pp. 122-129
Author(s):  
Alev Sakarya ◽  
Seyfettin Dalgic ◽  
Serap Senturk Dalgic
Keyword(s):  
Small Molecules ◽  
Recovery Time ◽  
Density Functional ◽  
Hexagonal Phase ◽  
Gold Surface ◽  
Dft Method ◽  
Absorption Energy ◽  
Short Recovery Time ◽  
The Stability ◽  
2D Nanosheets

Density functional theory (DFT) calculations were carried out to understand the structural stability of 2D nanosheets of gold and silver in hexagonal phase of 2H by the adsorption of small molecules. In this work, we have obtained the bonding and adsorption properties of such small molecules as H2O, H2O2, and C2H5OH on 2H phase of gold and silver nanosurfaces, through DFT method using Quantum Expresso (QE) code. The high absorption energy values of (-2.45 eV, -2,46 eV, -2, 41 eV) for H2O, H2O2, and C2H5OH molecules on 2H-Au surfaces, respectively obtained than that of 2H-silver surfaces that the interaction between small molecules and both 2H nanosurfaces corresponds to physisorption. However, during the adsorption, the gold surface in the 2H phase (2H-Au) seems to preserve its atomic structure, while 2H-Ag surface changes from 2H to the fcc structure. Based on the analysis of electronic and physicochemical properties, the composite systems of 2H-gold/2H-silver-small molecules exhibit semiconductor behaviour. While 2H-Ag surfaces have short recovery time values for hydrogen peroxide (H2O2), this time is quite long for 2H-Au surfaces. Because of the long recovery time, Au-2H reported surfaces can be a candidate for possible applications of viral capture. Thus, the reported results are significant, and they would stimulate the experimental and further studies.

Investigation on the Synthesize Reaction Possibility of M(CO)2CY-Ph3XR(M=Cr, Mn; X=Sn, Ge; Y=S, Se; R= N(C4H4), N(C8H6), C6H5)

2011 ◽  
Vol 396-398 ◽  
pp. 56-65
Author(s):  
Zheng Ping Wu ◽  
Ian S. Butler
Keyword(s):  
Total Energy ◽  
Benzene Ring ◽  
General Condition ◽  
Dft Method ◽  
Atomic Charges ◽  
Central Metal ◽  
Thermodynamics Properties ◽  
Key Factor ◽  
Calculation Results ◽  
Increasing Temperature

The thermodynamics properties of synthesize reactions of Ph3SnR (R= N (C4H4), N(C8H6), C6H5) and CpM(CO)2CY(M=Cr, Mn; Y=S, Se), the total energy and Mulliken atomic charges of the compound products M(CO)2CY-Ph3XR(M=Cr, Mn; X=Sn, Ge; Y=S, Se; R= N(C4H4), N(C8H6), C6H5) with different substitute positions on the benzene ring were investigated using DFT method. The calculation results of total energy showed that the ligand was determinant of the favourable substituted position and the central metal of two different type ligands CpCr(CO)2CY(Y=S, Se) and CpMn(CO)2 CY(Y=S, Se) was the key factor; whether the reactants Ph3SnR( R= N(C4H4), N(C8H6)) and Ph3SnR( R= C6H5) had the pyrrole or not had effect on the character of substituted position. The Mulliken atomic charges of central metal Sn and Ge showed that the atom charge value of Sn and Ge of M(CO)2CY-Ph4X was smaller than M(CO)2CY-Ph3XN (C4H4) and M(CO)2CY-Ph3XN(C8H6) (M=Cr, Mn; X=Sn, Ge; Y=S, Se) correspondingly; electron-donating trend of Ph3GeR group was stronger than that of Ph3SnR group; the pyrrole group had some conjugation effects which made the electronic distribute more even. The calculation results of thermodynamics properties of the synthesize reactions of Ph3SnR(R=N(C4H4), N(C8H6), C6H5) and CpCr(CO)CS showed that the reaction possibility was small at the general condition; ligand CpMn(CO)2CY(Y=S, Se) was more favorable to the reaction than CpCr(CO)2CY(Y=S, Se); different substituted positions would have effect on the reaction possibility apparently. Decreasing temperature would be favorable to the possibility of the reactions, but increasing temperature might be favourable to the rate of reactions.

Sign in / Sign up

Export Citation Format

Share Document