scholarly journals A study on structural and electronic properties of GaAs1-xNx and GaAs1-xBix alloys

2016 ◽  
Vol 4 (1) ◽  
pp. 6
Author(s):  
Metin Aslan ◽  
Battal Gazi Yalcin
Keyword(s):  
Electronic Properties ◽  
Density Functional ◽  
Local Density ◽  
Nitrogen Concentration ◽  
Potential Method ◽  
Generalized Gradient ◽  
Wide Range ◽  
Structural And Electronic Properties ◽  
Semiconductor Alloy ◽  
Ternary Semiconductor

<p>We have performed first principles method to investigate structural and electronic properties of GaAs<sub>1-x</sub>N<sub>x</sub> and GaAs<sub>1-x</sub>Bi<sub>x</sub> ternary semiconductor alloy using Density Functional Theory and pseudo potential method within the Generalized Gradient Approximations and Local Density Approximation. The Zinc-Blende phase is found stable for GaAsN and GaAsBi alloys. In this study we investigate the both bowing parameters changing with Bismuth concentration in GaAsBi and Nitrogen concentration in GaAsN alloys. By using the bowing parameter of GaAsBi and GaAsN alloys we obtained the bandgap energies for all x concentrations (0 &lt; x &lt; 1) and lattice constant of both alloys which are important for wide range device application. For studied materials, lattice parameters and band gap energies are compared with available theoretical and experimental works.</p>

scholarly journals Structural and Electronic Properties of Orthorhombic Phase Bi2Se3 Based On First-Principles Study

2019 ◽  
Vol 16 (2) ◽  
pp. 77 ◽  
Author(s):  
Muhammad Zamir Mohyedin ◽  
Afiq Radzwan ◽  
Mohammad Fariz Mohamad Taib ◽  
Rosnah Zakaria ◽  
Nor Kartini Jaafar ◽  
...  
Keyword(s):  
Electronic Properties ◽  
First Principles ◽  
Density Functional ◽  
Local Density ◽  
Computer Code ◽  
First Principles Calculation ◽  
Generalized Gradient ◽  
Exchange Correlation ◽  
Percentage Difference ◽  
Structural And Electronic Properties

Bi2Se3 is one of the promising materials in thermoelectric devices and very useful out of environmental concern due to its efficiency to perform at room temperature. Based on the first-principles calculation of density functional theory (DFT) by using CASTEP computer code, structural and electronic properties of Bi2Se3 were investigated. The calculation is conducted within the exchange-correlation of local density approximation (LDA) and generalized gradient approximation within the revision of Perdew-Burke-Ernzerhof (GGA-PBE) functional. It was found that the results are consistent with previous works of theoretical study with small percentage difference. LDA exchange-correlation functional method is more accurate and have a better agreement than GGA-PBE to describe the structural properties of Bi2Se3 which consist of lattice parameters. LDA functional also shown more accurate electronic structure of Bi2Se3 that consist of band structure and density of states (DOS) which consistent with most previous theoretical works with small percentage difference. This study proves the reliability of CASTEP computer code and show LDA exchange-correlation functional is more accurate in describing the nature of Bi2Se3 compared to the other functionals.

scholarly journals Comparative study of the structural and electronic properties of orthorhombic CH3NH3PbI3 hybrid perovskite for solar cell applications

2021 ◽  
Vol 40 (4) ◽  
pp. 616-622
Author(s):  
T.C. Chibueze
Keyword(s):  
Electronic Properties ◽  
Density Functional ◽  
Local Density ◽  
Total Density ◽  
Generalized Gradient ◽  
Lead Iodide ◽  
Functional Theory ◽  
Hybrid Perovskite ◽  
Structural And Electronic Properties ◽  
Direct Band

The structural and electronic properties of orthorhombic methyl ammonium lead iodide (CH3NH3PbI3 ) were investigated using the first principles density functional theory within the local density approximation (LDA) and the generalized gradient approximation (GGA).The lattice parameters obtained using the GGA were slightly greater than that obtained using the LDA. The total density of states and the electronic structure of the compound show that it is a direct band gap semiconductor. Our results are in agreement with the previous experimental and theoretical results and suggests that orthorhombic CH3NH3PbI3 compound is very promising in photovoltaic energy harvesting.

scholarly journals First-principle investigations of structural and electronic properties of TMAl (TM = Fe, Co, and Ni) transition metal aluminides

2015 ◽  
Vol 33 (2) ◽  
pp. 251-258
Author(s):  
Bendouma Doumi ◽  
Allel Mokaddem ◽  
Mustapha Ishak-Boushaki ◽  
Miloud Boutaleb ◽  
Abdelkader Tadjer
Keyword(s):  
Transition Metal ◽  
Electronic Properties ◽  
Density Functional ◽  
First Principle ◽  
Generalized Gradient ◽  
Metallic Behavior ◽  
Plane Wave Method ◽  
Structural And Electronic Properties ◽  
The Difference ◽  
Metal Aluminides

AbstractIn the present work, we have investigated the structural and electronic properties of TMAl (TM = Fe, Co, and Ni) transition metal aluminides in the B2 structure, using first-principle calculations of the density functional theory (DFT) based on the linearized augmented plane wave method (FP-LAPW) as implemented in the WIEN2k code, in which the energy of exchange and correlation are treated by the generalized gradient approximation (GGA), proposed in 1996 by Perdew, Burke and Ernzerhof (PBE). The ground state properties have been calculated and compared with other calculations, and the electronic structures of all FeAl, CoAl, and NiAl compounds exhibited a metallic behavior. It was depicted that the density of states is characterized by the large hybridization between the s-p (Al) and 3d (Fe, Co, and Ni) states, which creates the pseudogap in the region of anti-bonding states. Moreover, the band structures of FeAl, CoAl, and NiAl are similar to each other and the difference between them is in the energy level of each band relative to the Fermi level.

First principle study of the structural and electronic properties of Nihonium

MRS Advances ◽  
2020 ◽  
Vol 5 (23-24) ◽  
pp. 1175-1183
Author(s):  
Samuel A. Atarah ◽  
Martin N . H. Egblewogbe ◽  
Gebreyesus. G Hagoss
Keyword(s):  
Periodic Table ◽  
Density Functional ◽  
Local Density ◽  
Computational Study ◽  
Close Packing ◽  
Generalized Gradient ◽  
Packing Structure ◽  
Structural And Electronic Properties ◽  
Unit Cells ◽  
Total Energies

AbstractNihonium, Nh, is one of the newly synthesized elements. It has a high atomic number of 113, putting it in the same group as thallium, Tl. The properties of this element are largely unknown, and it is of interest to assess its (hypothetical) properties in the solid state. Elements in the same group of the periodic table as Nh are known to form binary and even tertiary compounds that have important semiconductor properties. This also makes studies on Nh attractive. We performed an ab initio computational study of its electronic structure adopting the local density and generalized gradient approximations for the exchange-correlation potential. The energy band diagrams, the total energies per volume of unit cells and density of states of Nh were compared to the known experimental and theoretical properties of elemental Tl , which lies in the same column above Nh in the periodic table. Within the limits of density-functional theory, it was found that solid Nh is expected to be a metal that is most stable in a hexagonal close packing structure.

FIRST-PRINCIPLE CALCULATION OF STRUCTURAL AND ELECTRONIC PROPERTIES OF ZINC-BLENDE ByAlxGa1-x-yN MATCHED TO AlN SUBSTRATE

2012 ◽  
Vol 26 (24) ◽  
pp. 1250159 ◽  
Author(s):  
LAKHDAR DJOUDI ◽  
ABDELHADI LACHEBI ◽  
BOUALEM MERABET ◽  
HAMZA ABID
Keyword(s):  
Electronic Properties ◽  
Density Functional ◽  
Strong Dependence ◽  
Theoretical Data ◽  
Lattice Parameter ◽  
Full Potential ◽  
Generalized Gradient ◽  
First Principle Calculation ◽  
Zinc Blende ◽  
Structural And Electronic Properties

The full-potential linearized augmented plane wave method (FP-LAPW) within density functional theory, using the generalized gradient approximation, is used to study the structural and electronic properties of zinc-blende B y Al x Ga 1-x-y N quaternary alloys that match the lattice of an AlN substrate. The range of compositions, for which the lattice of the alloy matches AlN , is determined. Our calculated band structure, density of states, electron density and lattice parameter for B y Al x Ga 1-x-y N allow to accurately evaluate the profound effect that the incorporation of small amounts of Boron have on structural and electronic properties of Al x Ga 1-x N alloys. A comparison of the ground state properties with the available experimental and theoretical data is made for the compounds related to B y Al x Ga 1-x-y N and of the Al x Ga 1-x N alloys. The results show a strong dependence of the band gap (as well as the lattice parameter) on the Boron content, which might make B y Al x Ga 1-x-y N materials promising and useful for optoelectronic applications.

Ab initio study of structural, mechanical, thermal and electronic properties of perovskites Sr(Li,Pd)H3

2016 ◽  
Vol 30 (04) ◽  
pp. 1650003 ◽  
Author(s):  
S. Benlamari ◽  
S. Amara Korba ◽  
S. Lakel ◽  
H. Meradji ◽  
S. Ghemid ◽  
...  
Keyword(s):  
Bulk Modulus ◽  
Electronic Properties ◽  
Elastic Constants ◽  
Density Functional ◽  
Electronic Band Structure ◽  
Local Density ◽  
Velocity Variation ◽  
Full Potential ◽  
Generalized Gradient ◽  
Electronic Band

The structural, elastic, thermal and electronic properties of perovskite hydrides SrLiH3 and SrPdH3 have been investigated using the all-electron full-potential linear augmented plane wave (FP-LAPW) method based on the density functional theory (DFT). For the exchange-correlation potential, local-density approximation (LDA) and generalized gradient approximation (GGA) have been used to calculate theoretical lattice parameters, bulk modulus, and its pressure derivative. The present results are in good agreement with available theoretical and experimental data. The three independent elastic constants [Formula: see text], [Formula: see text] and [Formula: see text] are also reported. From electronic band structure and density of states (DOSs), it is found that SrLiH3 is an insulator characterized by an indirect gap of 3.48 eV, while SrPdH3 is metallic with a calculated DOSs at Fermi energy of 0.745 states/eV-unit cell. Poisson’s ratio [Formula: see text], Young’s modulus (E), shear modulus (G), anisotropy factor (A), average sound velocities [Formula: see text] and density [Formula: see text] of these compounds are also estimated for the first time. The Debye temperature is deduced from the average sound velocity. Variation of elastic constants and bulk modulus of these compounds as a function of pressure is also reported. Pressure and thermal effects on some macroscopic properties are predicted using the quasi-harmonic Debye model.

Structural and Electronic Properties of Neptunium Sulphide: An Ab Initio Study

2016 ◽  
Vol 28 ◽  
pp. 23-26
Author(s):  
Chandrabhan Makode ◽  
Mahendra Aynyas ◽  
Jagdeesh Pataiya ◽  
Sankar P. Sanyal
Keyword(s):  
Phase Transition ◽  
Electronic Properties ◽  
Density Functional ◽  
Ambient Pressure ◽  
Energy Band Diagram ◽  
Lattice Parameter ◽  
Generalized Gradient ◽  
Transition Pressure ◽  
Phase Transition Pressure ◽  
Structural And Electronic Properties

The density functional theory within generalized gradient approximation (GGA) has been used to calculate lattice parameter, total energy, phase transition pressure and electronic properties of neptunium sulphide (NpS). From our calculations we observe that NpS is stable in NaCl – type structure under ambient pressure. For this compound, the phase transition pressure was found to be 29.5 GPa. The nature of metallic behaviour is remarked from energy band diagram in NpS. All properties obtained for this compound are in good agreement with available results.

scholarly journals High Pressure Study of Structural and Electronic Properties of PbSe

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
P. Bhambhani ◽  
K. Kabra ◽  
B. K. Sharma ◽  
G. Sharma
Keyword(s):  
High Pressure ◽  
Electronic Properties ◽  
Energy Gap ◽  
Electronic Band Structure ◽  
Local Density ◽  
Structural Phase ◽  
Generalized Gradient ◽  
Electronic Band ◽  
Structural And Electronic Properties ◽  
Direct Band

High pressure structural phase transition and electronic properties have been investigated using the linear combination of atomic orbitals (LCAO) method with two exchange-correlation approximations, the generalized gradient approximation (GGA) and local density approximation (LDA). The present study shows phase transitions from B1 to B27 and B27 to B2 at 6.24 GPa and 16.39 GPa, respectively. Lattice constant, bulk modulus, and energy gap of pressure-induced PbSe are found to be in good agreement with previous theoretical and experimental results. Variation of electronic band structure with pressure shows direct band gap along L point of the Brillouin zone.

FIRST-PRINCIPLES STUDY OF STRUCTURAL AND ELECTRONIC PROPERTIES OF SrLiSb UNDER HIGH PRESSURE

2012 ◽  
Vol 26 (29) ◽  
pp. 1250151
Author(s):  
Z. H. YU ◽  
C. Y. LI ◽  
H. Z. LIU
Keyword(s):  
High Pressure ◽  
Electronic Properties ◽  
First Principles ◽  
Density Functional ◽  
Geometry Optimization ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Electronic Phase ◽  
Structural And Electronic Properties

Using the first-principles plane wave pseudopotential method, the structural and electronic properties of intermetallic compound SrLiSb have been studied within generalized gradient approximation in the frame of density functional theory. The calculations of lattice parameters are in well agreement with the available experimental data. The geometry optimization results indicated the compressibility of SrLiSb is anisotropic under high pressure. The energy band structure and density of states of SrLiSb were also calculated, indicating that SrLiSb has an electronic phase transition from direct-gap semiconductor to indirect-gap semiconductor at approximate 8 GPa.

Sign in / Sign up

Export Citation Format

Share Document