Bulk moduli of wurtzite, zinc-blende, and rocksalt phases of ZnO from chemical bond method and density functional theory

2008 ◽  
Vol 92 (10) ◽  
pp. 101917 ◽  
Author(s):  
Changzeng Fan ◽  
Qiang Wang ◽  
Lixiang Li ◽  
Suhong Zhang ◽  
Yan Zhu ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Chemical Bond ◽  
Density Functional ◽  
Functional Theory ◽  
Zinc Blende ◽  
Bond Method

First-Principles Study on Initial Oxidation of NiAl(110)

2007 ◽  
Vol 546-549 ◽  
pp. 1455-1460 ◽  
Author(s):  
Jun Min Hu ◽  
Jia Xiang Shang ◽  
Yue Zhang ◽  
Chun Gen Zhou ◽  
Hui Bin Xu
Keyword(s):  
Density Functional Theory ◽  
Charge Transfer ◽  
Oxygen Atom ◽  
Chemical Bond ◽  
First Principles ◽  
Density Functional ◽  
Bridge Site ◽  
Initial Oxidation ◽  
Functional Theory ◽  
Oxidation Stage

The oxygen atom adsorption at Al-Al bridge, Ni-Ni bridge, Al top and Ni top site on the NiAl(110) surface by first-principles method within density functional theory has been studied in this paper. It has been found that the preferred adsorption position of the oxygen was at the Al-Al bridge site then the Ni-Ni bridge site. The charge transfer took place obviously between the O atom and the nearest Al atoms, but no charge transferred from the nearest Ni atoms to O atom. For the Al-Al (Ni-Ni) bridge adsorption site, the bond lengths of Al-O and Ni-O were about 1.741 Å (1.700Å) and 2.369Å (2.012Å), respectively, which means that the Al atom is easier to be oxidized than the Ni atom. It is revealed that the Al atom oxidized selectively and the chemical bond formed between the O ion and the nearest Al ions during the initial oxidation stage.

Reconstruction of Nonpolar Gan Surfaces

1996 ◽  
Vol 423 ◽  
Author(s):  
J. Elsner ◽  
M. Haugk ◽  
Th. Frauenheim
Keyword(s):  
Density Functional Theory ◽  
Bond Length ◽  
Density Functional ◽  
Rotation Angle ◽  
Tight Binding ◽  
Functional Theory ◽  
Zinc Blende ◽  
Nonpolar Gan

AbstractA density-functional theory based nonorthogonal tight-binding scheme is used to investigate the nonpolar surfaces of GaN in the wurtzite and zinc-blende phases. In III-V semiconductors the nonpolar surfaces mainly reconstruct by a bond-length conserving rotation of the surface atoms. In contrast to that for all nonpolar GaN surfaces this bond-length is shortened by ≈3 − 4%. We furthermore find the rotation angle to be significantly smaller than could be expected from results for GaAs and GaP.

Energy analysis of the chemical bond in group IV and V complexes: A density functional theory study

2005 ◽  
Vol 101 (6) ◽  
pp. 869-877 ◽  
Author(s):  
O. Kh. Poleshchuk ◽  
E. L. Shevchenko ◽  
V. Branchadell ◽  
M. Lein ◽  
G. Frenking
Keyword(s):  
Density Functional Theory ◽  
Chemical Bond ◽  
Density Functional ◽  
Energy Analysis ◽  
Group Iv ◽  
Density Functional Theory Study ◽  
Functional Theory

Simulation BeSe Nanowires in Two Phasese Zinc-Blende and Wurtzite Using Density Functional Theory

2011 ◽  
Vol 110-116 ◽  
pp. 1264-1269
Author(s):  
Mina Alimohammadi ◽  
Ali Mokhtari
Keyword(s):  
Density Functional Theory ◽  
Cohesive Energy ◽  
Density Functional ◽  
Energy Gap ◽  
Side Surface ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Bulk State ◽  
Zinc Blende ◽  
Two Phases

In this work, we are reporting on the simulation of the beryllium selenide (BeSe) nanowires (NWs) by computational package Q-Espresso / PWSCF according to the ab-initio calculations. Structural and electronic properties, including cohesive energy and Density Of State (DOS) BeSe NWs in two phases on the zinc–blende (ZB) and wurtzite (WZ), using density functional theory based on pseudo-potential approximation and generalized gradient approximation (GGA) up to 20 angstrom in diameter has been calculated. Due to dangling bonds (DBs) in the side surface NWs, cohesive energy is obtained less than the amount of this energy in bulk state of this compound, but with increasing diameter of NWs, the amount of this energy will approach to the bulk state. Comparison of cohesive energy with beryllium selenide NWs in two phases, we find these NWs in WZ phase is more stable and have good compatibility for this result with other results in NWs of similar compounds. The value of energy gap in these NWs on various diameters is obtained less than the amount of the bulk state. It is observed that by increasing the diameter of NWs, the cohesive energy approaches to its value in bulk state.

First-principles calculations for the structural and electronic properties of GaAs1−xPx nanowires

2016 ◽  
Vol 27 (03) ◽  
pp. 1650035 ◽  
Author(s):  
Rezek Mohammad ◽  
Şenay Katırcıoğlu
Keyword(s):  
Density Functional Theory ◽  
Electronic Properties ◽  
First Principles ◽  
Density Functional ◽  
Band Gaps ◽  
First Principles Calculations ◽  
Functional Theory ◽  
Quantum Size ◽  
Zinc Blende ◽  
Structural And Electronic Properties

Structural stability and electronic properties of GaAs[Formula: see text]P[Formula: see text] ([Formula: see text]) nanowires (NWs) in zinc-blende (ZB) ([Formula: see text] diameter [Formula: see text][Formula: see text]Å) and wurtzite (WZ) ([Formula: see text][Formula: see text]Å) phases are investigated by first-principles calculations based on density functional theory (DFT). GaAs ([Formula: see text]) and GaP ([Formula: see text]) compound NWs in WZ phase are found energetically more stable than in ZB structural ones. In the case of GaAs[Formula: see text]P[Formula: see text] alloy NWs, the energetically favorable phase is found size and composition dependent. All the presented NWs have semiconductor characteristics. The quantum size effect is clearly demonstrated for all GaAs[Formula: see text]P[Formula: see text] ([Formula: see text]) NWs. The band gaps of ZB and WZ structural GaAs compound NWs with [Formula: see text] diameter [Formula: see text][Formula: see text]Å and [Formula: see text][Formula: see text]Å, respectively are enlarged by the addition of concentrations of phosphorus for obtaining GaAs[Formula: see text]P[Formula: see text] NWs proportional to the x values around 0.25, 0.50 and 0.75.

Density functional theory modeling of C–Au chemical bond formation in gold implanted polyethylene

2017 ◽  
Vol 19 (42) ◽  
pp. 28897-28906 ◽  
Author(s):  
Andrej Antušek ◽  
Martin Blaško ◽  
Miroslav Urban ◽  
Pavol Noga ◽  
Danilo Kisić ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Ion Implantation ◽  
Chemical Bond ◽  
Density Functional ◽  
Bond Formation ◽  
Theoretical Chemistry ◽  
Functional Theory ◽  
Chemical Bond Formation ◽  
Gold Ion

We have studied processes of gold ion implantation in polyethylene (PE) by theoretical chemistry methods.

Thermodynamic properties of ZnTe in zinc-blende and wurtzite phases

2016 ◽  
Vol 30 (21) ◽  
pp. 1650147 ◽  
Author(s):  
S. Ferahtia ◽  
S. Saib ◽  
N. Bouarissa
Keyword(s):  
Density Functional Theory ◽  
First Principles ◽  
Density Functional ◽  
Local Density ◽  
Density Approximation ◽  
First Principles Calculations ◽  
Functional Theory ◽  
Zinc Blende ◽  
The Density Functional Theory ◽  
Two Phases

The present study deals with first-principles calculations of the thermal properties of ZnTe in the two phases namely, zinc-blende and wurtzite. The calculations are mainly performed using the density functional theory with the local density approximation and response-function calculations. The full phonon dispersions throughout the Brillouin zone are presented. The temperature dependence of the lattice parameters, bulk modulus, entropy and heat capacity are examined and discussed. Our findings agree reasonably well with those available in the literature.

Sign in / Sign up

Export Citation Format

Share Document