Studying of B, N, S, Si and P Doped (5, 5) Carbon Nanotubes by the Density Functional Theory

2012 ◽  
Vol 463-464 ◽  
pp. 1488-1492 ◽  
Author(s):  
Yan Li Wang ◽  
Ke He Su ◽  
Jun Ping Zhang
Keyword(s):  
Carbon Nanotubes ◽  
Density Functional Theory ◽  
Density Functional ◽  
Periodic Boundary ◽  
Energy Gap ◽  
Periodic Boundary Conditions ◽  
Functional Theory ◽  
Energy Gaps ◽  
The Density Functional Theory ◽  
Metal Conductivity

The B, N, S, Si and P atoms doped single walled (5, 5) carbon nanotubes were studied by density functional theory B3LYP/3-21G (d) with the periodic boundary conditions. The ultra long tube models were calculated and the structures, energies and the band structures were obtained. The N, Si and S doped nanotubes have narrow energy gap with metal conductivity whereas B and P doped nanotubes have overlapped energy gaps with or semi-metal conductivity.

scholarly journals Chloroquine drug and Graphene complex for treatment of COVID-19

2020 ◽  
Author(s):  
Saeedeh Mohammadi ◽  
Mohammad Esmailpour ◽  
Mina Mohammadi
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Energy Gap ◽  
Dft Method ◽  
Complex State ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Structural And Electrical Properties ◽  
Suitable Structure ◽  
Drug Complex

Abstract This paper is a new step in helping the treatment of coronavirus by improving the performance of chloroquine drug. For this purpose, we propose a complex of chloroquine drug with graphene nanoribbon (GNR) scheme. We compute the structural and electrical properties and absorption of chloroquine (C18H26ClN3) and GNR complex using the density functional theory (DFT) method. By creating a drug and GNR complex, the density of states of electrons increases and the energy gap decreases compared to the chloroquine. Also, using absorption calculations and spectrums such as infrared and UV-Vis spectra, we showed that GNR is a suitable structure for creating chloroquine drug complex. Our results show that the dipole moment, global softness and electrophilicity for the drug complex increases compared to the non-complex state. Our calculations can be useful for increasing performance and reducing the side effects of chloroquine, and thus can be effective in treating coronavirus.

scholarly journals A NOVEL FRACTAL GEOMETRY DOPING FOR GRAPHENE NANORIBBON AND THE OPTIMIZATION OF CRYSTAL: A DENSITY FUNCTIONAL THEORY (DFT) STUDY

2020 ◽  
Vol 17 (35) ◽  
pp. 1148-1158
Author(s):  
Mohammed L. JABBAR ◽  
Kadhum J. AL-SHEJAIRY
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Energy Gap ◽  
Minimum Energy ◽  
Graphene Nanoribbon ◽  
Chemical Doping ◽  
Functional Theory ◽  
Lower Reactivity ◽  
The Density Functional Theory ◽  
Semiconductor Behavior

Chemical doping is a promising route to engineering and controlling the electronic properties of the zigzag graphene nanoribbon (ZGNR). By using the first-principles of the density functional theory (DFT) calculations at the B3LYP/ 6-31G, which implemented in the Gaussian 09 software, various properties, such as the geometrical structure, DOS, HOMO, LUMO infrared spectra, and energy gap of the ZGNR, were investigated with various sites and concentrations of the phosphorus (P). It was observed that the ZGNR could be converted from linear to fractal dimension by using phosphorus (P) impurities. Also, the fractal binary tree of the ZGNR and P-ZGNR structures is a highlight. The results demonstrated that the energy gap has different values, which located at this range from 0.51eV to 1.158 eV for pristine ZGNR and P-ZGNR structures. This range of energy gap is variable according to the use of GNRs in any apparatus. Then, the P-ZGNR has semiconductor behavior. Moreover, there are no imaginary wavenumbers on the evaluated vibrational spectrum confirms that the model corresponds to minimum energy. Then, these results make P-ZGNR can be utilized in various applications due to this structure became more stable and lower reactivity.

Ab initio study of hydrogen chemisorption in nitrogen-doped carbon nanotubes

2016 ◽  
Vol 18 (36) ◽  
pp. 25663-25670 ◽  
Author(s):  
Julian David Correa ◽  
Elizabeth Florez ◽  
Miguel Eduardo Mora-Ramos
Keyword(s):  
Carbon Nanotubes ◽  
First Principles ◽  
Density Functional ◽  
Periodic Boundary ◽  
Periodic Boundary Conditions ◽  
Hydrogen Chemisorption ◽  
Ab Initio Study ◽  
Functional Theory ◽  
Nitrogen Doped ◽  
Nitrogen Doped Carbon

The electronic structure of single walled nitrogen-doped carbon nanotubes is calculated by first principles using density functional theory within the supercell approach with periodic boundary conditions.

A Density Functional Theory Study on the Structures and Electronic Properties of XAln (X = Br, I; n = 3–15) Clusters

2019 ◽  
Vol 74 (2) ◽  
pp. 121-129 ◽  
Author(s):  
Ming Hui ◽  
Qing-Huai Zhao ◽  
Zhi-Peng Wang ◽  
Shuai Zhang ◽  
Gen-Quan Li
Keyword(s):  
Density Functional Theory ◽  
Electronic Properties ◽  
Density Functional ◽  
Energy Gap ◽  
Three Dimensional ◽  
Density Functional Theory Calculations ◽  
Chemical Hardness ◽  
Geometrical Structures ◽  
Functional Theory ◽  
The Density Functional Theory

AbstractThe effects of halogen element X (X = Br, I) doping on the geometrical structures and electronic properties of neutral aluminium clusters are systematically studied by utilising the density functional theory calculations. The structures of X-doped clusters show the three-dimensional forms with increasing atomic number except for n = 3 and X (X = Br, I) atom prefer to occupy the surface site of the host Aln clusters. BrAl7 and IAl7 clusters are the most stable geometries. The HOMO-LUMO energy gap and chemical hardness show an odd–even alternative phenomenon. The charges always transfer from the Al atoms to the X (X = Br, I) atom. Finally, the dipole and polarisability are discussed.

A Density Functional Theory Study on the Ultra Long Single Walled Armchair (3, 3) (Bn)Xcy Nanotubes

2012 ◽  
Vol 463-464 ◽  
pp. 1435-1439
Author(s):  
Yan Li Wang ◽  
Ke He Su ◽  
Xin Wang
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Energy Gap ◽  
Tube Model ◽  
Functional Theory ◽  
Atom Ratio ◽  
Energy Gaps ◽  
Different Types ◽  
C And N ◽  
Semiconductor Conductivity

The single walled armchair (3,3) (BN)xCy nanotubes with different ratios of B, C and N atoms were studied with density functional theory of B3LYP/3-21G(d) combined with the periodic boundary conditions in simulating the ultra long tube model. Different types of twelve models were examined and the diameter, energy, energy gaps and the band structures were obtained. The energy gaps were within 0.203eV to 2.620eV showing semiconductor conductivity. Results show that the energy gap and the band structure depend on both the atom ratio and arrangement.

scholarly journals Distribution of dopant ions around poly(3,4-ethylenedioxythiophene) chains: a theoretical study

2017 ◽  
Vol 19 (15) ◽  
pp. 9889-9899 ◽  
Author(s):  
Jordi Casanovas ◽  
David Zanuy ◽  
Carlos Alemán
Keyword(s):  
Density Functional Theory ◽  
Boundary Conditions ◽  
Dft Calculations ◽  
Density Functional ◽  
Periodic Boundary ◽  
Theoretical Study ◽  
Periodic Boundary Conditions ◽  
Polymer Chains ◽  
Functional Theory

The effect of counterions and multiple polymer chains on the properties and structure of poly(3,4-ethylenedioxythiophene) (PEDOT) doped with ClO4− has been examined using density functional theory (DFT) calculations with periodic boundary conditions (PBCs).

Adsorption of Sulfur’s Atoms on the Outer Surface of Carbon Nanotubes

2015 ◽  
Vol 1091 ◽  
pp. 25-29
Author(s):  
Sergey Anatolevich Sozykin ◽  
Valeriy Petrovich Beskachko
Keyword(s):  
Carbon Nanotubes ◽  
Ground State ◽  
Density Functional ◽  
Periodic Boundary Conditions ◽  
Chemical Bonds ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
The Moment ◽  
Ribbon Structures ◽  
Slight Deformation

The article is about regularities of structure formation of carbon nanotubes (7,7) in their ground state in the process of the gradually increasing of the concentration of sulfur atoms. The fragment of nanotube is investigated within the framework of the density functional theory with the using of periodic boundary conditions. It contains 112 carbon atoms and n = 1 ÷ 9 sulfur atoms. It is shown that the most energetically favorable configurations of n = 1 ÷ 6 sulfur atoms can be considered as a configuration uncombined sulfur clusters Sn with the slight deformation by tube field. From n = 6, there is a tendency toward the formation of a ribbon structures with 2 sulfur atoms wide, it has a tendency in the moment of increasing n to be guided by transversely to the tube axis. In all considered cases the sulfur atoms are located at a distance from the surface of the tube more than 0.28 nm, it is excluded the possibility of the formation of the strong (covalent) chemical bonds with the carbon nanotube.

A computational study of bulk porous two-dimensional polymers related to graphyne

2016 ◽  
Vol 18 (31) ◽  
pp. 21305-21314 ◽  
Author(s):  
A. Sánchez-González ◽  
J. A. Dobado ◽  
M. Torneiro
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Periodic Boundary ◽  
Computational Study ◽  
Periodic Boundary Conditions ◽  
Two Dimensional ◽  
Functional Theory ◽  
Carbon Allotrope ◽  
Triple Bonds ◽  
2D Polymers

We use density functional theory methods with periodic boundary conditions to investigate the stacking arrangements of the bulk 2D polymers multilayer porous graphyne, the analog in which the triple bonds are substituted by double bonds and the related carbon allotrope multilayer graphyne.

Sign in / Sign up

Export Citation Format

Share Document