Electronic Structure and Mechanical Properties of Zircaloy-2 and Zircaloy-4: A First Principle Study

2013 ◽  
Author(s):  
Chunhai Lu ◽  
Wenkai Chen ◽  
Min Chen ◽  
Shijun Ni ◽  
Chengjiang Zhang
Keyword(s):  
Mechanical Properties ◽  
Electronic Structure ◽  
Zirconium Alloy ◽  
Local Density ◽  
Partial Density ◽  
Total Density ◽  
First Principle ◽  
Density Of State ◽  
Virtual Crystal Approximation ◽  
Anisotropic Mechanical Properties

The local-density approximation (LDA) coupled with the virtual crystal approximation (VCA) method electronic structure is applied to evaluate elastic constants, bulk modulus, shear modulus, Young’s modulus and Poisson’s ratio mechanic properties of metal zirconium, Zircaloy-2 and Zircaloy-4. The results show that there is no obvious difference in band structure and total density of state (DOS) between metal zirconium and zirconium alloy. However, p and d electron partial density of state (PDOS) presents the slight difference between metal zirconium and zirconium alloy. Zircaloy-2 and Zircaloy-4 present better elastic mechanical properties than metal zirconium. The metal zirconium and zirconium alloy show the anisotropic mechanical properties.

Density Function Theory Calculation of Crystal Properties and Electronic Structure of δ-Pu

2017 ◽  
Vol 727 ◽  
pp. 712-717
Author(s):  
Yuan Jiang Zhu ◽  
Yun Liang Gao
Keyword(s):  
Electronic Structure ◽  
Density Function ◽  
Elastic Properties ◽  
Density Functional ◽  
Function Theory ◽  
Local Density ◽  
Density Function Theory ◽  
Partial Density ◽  
Density Of State ◽  
Lattice Constants

In this paper, lattice constants, elastic properties and electronic structure of δ-Pu are investigated by means of plane wave pseudo-potential method (PWP) based on density function theory (DFT). A variety of density functional theory methods have been adopted to calculate the crystal structure and elastic property of δ-Pu, and it is found that the lattice constants, bulk modulus B, shear modulus G, Young's modulus E and Poisson's ratio ν calculated by spin polarization local density approximation (SP+LDA) method are in best agreement with experimental values. The electronic structure have been investigated within the framework of LDA+U, and the band structure, density of state (DOS) and partial density of state (PDOS) are calculated. Calculation results of elastic properties and electronic structure show that, δ-Pu shows obvious metallicity and well ductility, its electrons are strongly corrected and the DOS in the vicinity of the Fermi Level is mainly contributed by 5f electrons.

scholarly journals Density functional theory study of electronic properties of Bi2Se3 and Bi2Te3

2017 ◽  
Vol 12 (3) ◽  
Author(s):  
Abdullahi Lawal ◽  
Amiruddin Shaari
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Topological Insulators ◽  
Van Der Waals Interactions ◽  
Partial Density ◽  
Total Density ◽  
Density Of State ◽  
Generalized Gradient ◽  
Linear Dispersion ◽  
Functional Theory

Topological insulators are layered materials via van der Waals interactions with hexagonal unit cell similar to that of graphene. The exciting features of Bi2Se3 and Bi2Te3 topological insulators their zero band gap surface states exhibiting linear dispersion at the Fermi energy. We present here first principles study pertaining to electronics properties of Bi2Se3 and Bi2Te3 compound with and without spin-orbit interaction using density functional theory (DFT). Total density of state (DOS), partial density of state (PDOS) and band structure where determined by Quantum-Espresso simulation package which uses plane wave basis and pseudopotential for the core electrons, while treating exchange-correlation potential with generalized gradient approximation (GGA). From our computations, the obtained results were found to be consistent with the available experimental results. 

scholarly journals First-Principles Study on the Mechanical Properties and Electronic Structure of V Doped WCoB and W2CoB2 Ternary Borides

Materials ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 967 ◽  
Author(s):  
Tong Zhang ◽  
Haiqing Yin ◽  
Cong Zhang ◽  
Ruijie Zhang ◽  
Xue Jiang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Electronic Structure ◽  
Shear Modulus ◽  
Density Of States ◽  
Formation Energy ◽  
Partial Density ◽  
Doping Content ◽  
Transition Elements ◽  
Covalent Bonds ◽  
Ternary Boride

For the purpose of exploring new hard materials and doping methods, the structural, mechanical and electronic properties of WCoB and W2CoB2 ternary boride were investigated with 0, 8.33, 16.67, 25 and 33.33 at.% V doping content and W2CoB2 with 0, 5, 10, 15 and 20 at.% V doping content by first-principle calculations. The cohesive energy, impurity formation energy and formation energy indicate the structural stability of V doped WCoB and W2CoB2. The elastic constants and mechanical properties imply that V doping leads to the decrement of shear modulus and the increment of ductility. Two different kinds of hardness models verify that V doping contributes to the decrement of hardness, which is closely related to shear modulus. The electronic structure is analyzed by DOS (density of states), PDOS (partial density of states) and charge density difference, which indicate the formation of weaker B–V covalent bonds, W–V and W–W metallic bonds lead to the decrement of mechanical properties. Compared with previous studies of Cr, Mn doped WCoB and W2CoB2, V doping leads to worse mechanical properties and hardness, indicating V may not be a suitable choice of doping transition elements.

First-Principles Study of Electronic Structure and Optical Properties of V-Doped CrSi2

2015 ◽  
Vol 1104 ◽  
pp. 125-130 ◽  
Author(s):  
Fang Gui ◽  
Shi Yun Zhou ◽  
Wan Jun Yan ◽  
Chun Hong Zhang ◽  
Shao Bo Chen
Keyword(s):  
Optical Properties ◽  
Electronic Structure ◽  
Density Of States ◽  
Density Functional ◽  
Partial Density ◽  
Optical Parameters ◽  
Total Density ◽  
Type Semiconductor ◽  
Refractive Index Increase ◽  
P Type

The electronic structure and optical properties of V-doped CrSi2 have been calculated by using the first-principle peudo-potential plane-wave method based on the density functional theory.The parameters and properties of structure were given and the theory data were offered to research the effect of V doping into CrSi2. The calculations of energy band structure, total density of states, partial density of states of V-doped CrSi2were analysed. Fermi level enters into valence band which makes the V-doped CrSi2to be p-type semiconductor that improves the electrical conductivity of material. Additionally, the optical parameters of V-doped CrSi2were also discussed. It was found that both static dielectric constant and static refractive index increase after doping.

A First-Principle Study of Fe-Doped Co3O4 on N-Doped Graphene as Electrocatalyst

2021 ◽  
Vol 897 ◽  
pp. 95-100
Author(s):  
Chun Ying Wang
Keyword(s):  
Catalytic Mechanism ◽  
Partial Density ◽  
First Principle ◽  
Fe Doping ◽  
Density Of State ◽  
Principle Calculation ◽  
First Principle Calculation ◽  
Doped Graphene ◽  
Adsorption Energies ◽  
Zinc Air Batteries

The metal-air batteries, especially the Zinc-air batteries, are great solutions to the growing energy crisis with excellent rechargeable capacity. ORR is the key electro-chemical reaction in Zinc-air batteries, and the development of the ORR efficiency is being studied extensively. The doping of transition metal in Co3O4, with the basement of N-doped graphene have been confirmed to have catalytic activity which can be comparable to Pt/C. Herein, the Fe-doped Co3O4 supported by N-doped graphene is constructed as the catalyst of ORR, and that without Fe doping is also constructed as comparison. Through first-principle calculation, it shows that the adsorption energies to O2 on the same site of each surface and on different sites on Fe-doped one. The partial density of state of the O2 adsorption system shows the effects of electron transfer and orbital hybridization on catalysis, which provide evidence to the catalytic mechanism with Fe doping. The energy changes of each step in ORR on catalyst with Fe doping and without Fe doping show the shortcomings of the simulation, including the spin of Fe atoms. Thus the study confirms that the adding of Fe contributes to the catalystic capability compared to the pure Co3O4.

Structure Stability and Electronic Structure of Semiconducting Rhenium Silicide with Doping

2007 ◽  
Vol 26-28 ◽  
pp. 1029-1032 ◽  
Author(s):  
An Ning Qiu ◽  
Lan Ting Zhang ◽  
Jian Sheng Wu
Keyword(s):  
Electronic Structure ◽  
Fermi Level ◽  
Local Density ◽  
Structure Stability ◽  
Full Potential ◽  
Density Of State ◽  
Al Doping ◽  
Augmented Plane Wave ◽  
Semiconductor Behavior ◽  
Linearized Augmented Plane Wave

Full-potential linearized augmented plane-wave (FP-LAPW) method within the local density approximation plus self-interaction correction (LDA+USIC) has been applied to study the structure stability and electronic structure of ReSi1.75 and its doped systems with Al and Mo. Structural relaxation results show that the vacancy prefers to occupy the Si3 and Si4 site in the lattice with little ordering. For doping systems, Al prefers to substitute for Si at the Si3 site and Mo prefers to substitute for Re at the Re1 site. ReSi1.75 shows narrow gap semiconductor behavior with an indirect gap of 0.12 eV and a direct gap of 0.36 eV. Al doping compound remains semiconductor while Mo doping compound has a tendency to change into semimetals or metals. The Fermi level of doped systems moves into the valence band resulting in an increase of density of state at the Fermi level. It will enhance the thermoelectric properties and agrees well with the experiment results.

First-principle investigation of electronic structure and mechanical properties of AlMgB14

2009 ◽  
Vol 1224 ◽  
Author(s):  
Liwen F Wan ◽  
Scott P Beckman
Keyword(s):  
Mechanical Properties ◽  
Electronic Structure ◽  
Ab Initio ◽  
Density Of States ◽  
Fermi Energy ◽  
First Principle ◽  
Metal Atoms ◽  
Structural And Electronic Properties ◽  
The Impact ◽  
Atomic And Electronic Structure

AbstractThe structural and electronic properties of AlMgB14 are investigated using ab initio methods. The impact of vacancies and electron doping on the crystal’s atomic and electronic structure is investigated. It is found that removing metal atoms does not influence the density of states, except for changes to the Fermi energy. The density of states of the off-stoichiometric Al0.75Mg0.75B14 crystal and the AlMgB14 crystal with five electrons removed are nearly identical. The removal of six electrons results in an 11% contraction in the crystal’s volume. This is associate with the removal of electrons from the B atoms’ 2p-states.

Sign in / Sign up

Export Citation Format

Share Document