FIRST-PRINCIPLE STUDY OF STRUCTURAL AND ELECTRONIC PROPERTIES OF CUBIC STRONTIUM TITANATE

We have performed ab-initio investigation of SrTiO3 with cubic structure, and have computed its structural and electronic properties. The calculations are performed using a plane wave expansion within the local density approximation and the pseudopotential approximation. Results are given for the lattice constant, bulk modulus and charge density. The lattice parameter and bulk modulus calculated for SrTiO3within LDA are 3.908 Å and 184.6832 GPa respectively. It is found that the calculated lattice parameter and bulk modulus are in good agreement with the available experimental data. The charge density plots show higher accumulation of charge around the boundary and corners. All these calculations have been carried out using ABINIT computer code.

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

Scientific Research Journal ◽

10.24191/srj.v16i2.6359 ◽

2019 ◽

Vol 16 (2) ◽

pp. 77 ◽

Cited By ~ 1

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.

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Assessment of Functionals for First-Principle Studies of the Structural and Electronic Properties ofδ-Bi2O3

Advances in Condensed Matter Physics ◽

10.1155/2015/120294 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9

Author(s):

D. H. Galván ◽

R. Núñez-González ◽

R. Rangel ◽

P. Alemany ◽

A. Posada-Amarillas

Keyword(s):

Band Structure ◽

Charge Density ◽

Electronic Properties ◽

Density Of States ◽

Lattice Parameter ◽

Experimental Result ◽

Ionic Character ◽

High Symmetry ◽

Density Profiles ◽

Structural And Electronic Properties

Fully relativistic full-potential density functional calculations with an all-electron linearized augmented plane waves plus local orbitals method were carried out to perform a comparative study on the structural and electronic properties of the cubic oxideδ-Bi2O3phase, which is considered as one of the most promising materials in a variety of applications including fuel cells, sensors, and catalysts. Three different density functionals were used in our calculations, LDA, the GGA scheme in the parametrization of Perdew, Burke, and Ernzerhof (PBE96), and the hybrid scheme of Perdew-Wang B3PW91. The examined properties include lattice parameter, band structure and density of states, and charge density profiles. For this modification the three functionals reveal the characteristics of a metal and the existence of minigaps at high symmetry points of the band structure when spin-orbit coupling is taken into account. Density of states exhibits hybridization of Bi 6s and O 2p orbitals and the calculated charge density profiles exhibit the ionic character in the chemical bonding of this compound. The B3PW91 hybrid functional provided a better agreement with the experimental result for the lattice parameter, revealing the importance of Hartree-Fock exchange in this compound.

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Ab initio studies of the structural, electronic, and optical properties of quaternary BxAlyGa1–x–yN compounds

Zeitschrift für Naturforschung B ◽

10.1515/znb-2015-0149 ◽

2016 ◽

Vol 71 (2) ◽

pp. 125-134 ◽

Cited By ~ 2

Author(s):

M’hamed Larbi ◽

Rabah Riane ◽

Samir F. Matar ◽

Ahmed Abdiche ◽

Mustapha Djermouni ◽

...

Keyword(s):

Bulk Modulus ◽

Local Density ◽

Lattice Parameter ◽

Band Gaps ◽

Full Potential ◽

Generalized Gradient ◽

Augmented Plane Wave ◽

Plane Wave Method ◽

Structural And Electronic Properties ◽

Linearized Augmented Plane Wave

AbstractOriginal first-principles calculations were performed to study the structural and electronic properties of quaternary BxAlyGa1–x–yN compounds, using the non-relativistic full-potential linearized augmented plane wave method as employed in the Wien2k code. For the exchange-correlation potential, local density approximation and generalized gradient approximation have been used to calculate theoretical lattice parameters, bulk modulus, and their pressure derivatives. Non-linear variation with compositions x and y of the lattice parameter, bulk modulus, and direct and indirect band gaps have been found. The calculated bowing of the fundamental band gaps is in good agreement with the available experimental and theoretical values.

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Structural and Electronic Properties of Thulium Compounds

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.28.59 ◽

2016 ◽

Vol 28 ◽

pp. 59-64

Author(s):

Yeshvir Singh Panwar ◽

Mahendra Aynyas ◽

Jagdeesh Pataiya ◽

Sankar P. Sanyal

Keyword(s):

Bulk Modulus ◽

Local Density ◽

Structural Phase ◽

Tight Binding ◽

Energy Band Diagram ◽

Lattice Parameter ◽

Band Diagram ◽

Cscl Type ◽

Structural And Electronic Properties ◽

Lmto Method

The tight binding linear muffin-tin-orbital (TB-LMTO) method within the local density approximation (LDA) is used to study the electronic structure and high pressure behaviour of thulium compounds TmX (X= P, As, S, and Se). We also predict a structural phase transition from NaCl to CsCl-type structure. The transition pressures were found to be 40.0, 31.0, 58.0 and 49.0 GPa, for TmP, TmAs, TmS and TmSe respectively. Apart from this, the lattice parameter (a0), bulk modulus (B0), band structure and density of states are calculated. From energy band diagram, it is observed that these compounds exhibit weak metallic character. The calculated values of lattice parameters and bulk modulus are of reasonable agreement with available data.

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Pressure Induced Structural and Electronic Properties of Thulium Nitride

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1047.147 ◽

2014 ◽

Vol 1047 ◽

pp. 147-150

Author(s):

Yeshvir Singh Panwar ◽

Mahendra Aynyas ◽

M.K. Tejraj ◽

S.P. Sanyal

Keyword(s):

Phase Transition ◽

Bulk Modulus ◽

Electronic Properties ◽

Structural Phase Transition ◽

Phase Structure ◽

Local Density ◽

Ambient Pressure ◽

Structural Phase ◽

Lattice Parameter ◽

Type B

We report ab initio calculations of pressure induced structural phase transition and electronic properties of thulium nitride (TmN). The total energy as a function of volume is obtained by using the self-consistent tight binding linear muffin-tin-orbital (TB-LMTO) method within the local density approximation (LDA). It is found that TmN is stable in NaCl – type structure under ambient pressure. We predict a structural phase transition from NaCl-type (B1-phase) structure to CsCl-type (B2-phase) structure of this compound at a high pressure of 68 GPa. We also calculate the lattice parameter (a0), bulk modulus (B0), band structure and density of states. From energy band diagram it is observed that TmN exhibit metallic behaviour. The calculated values of equilibrium lattice parameter and bulk modulus are in general good agreement with available experimental data.

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First-Principles Investigation on Elastic Constants of TiN under High Pressure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.802.109 ◽

2013 ◽

Vol 802 ◽

pp. 109-113

Author(s):

Kittiya Prasert ◽

Pitiporn Thanomngam ◽

Kanoknan Sarasamak

Keyword(s):

Elastic Constants ◽

First Principles ◽

Local Density ◽

Ambient Pressure ◽

Lattice Parameter ◽

First Principles Calculations ◽

Generalized Gradient ◽

Generalized Gradient Approximation ◽

Shear Distortion ◽

Calculated Lattice Parameter

Elastic constants of NaCl-type TiN under pressure were investigated by first-principles calculations within both local density approximation (LDA) and Perdew-Burke-Ernzerhof generalized-gradient approximation (PBE-GGA). At ambient pressure, the calculated lattice parameter, bulk modulus, and elastic constants of NaCl-type TiN are in well agreement with other available values. Under pressure, all elastic constants,C11,C12, andC44, are found to increase with pressure.C11, which is related to the longitudinal distortion, increases rapidly with pressure whileC12andC44which are related to the transverse and shear distortion, respectively, are much less sensitive to pressure.

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COMPARATIVE STUDY OF THE STRUCTURAL AND ELECTRONIC PROPERTIES OF BN(5, 5) AND C(5, 5) NANOTUBES UNDER PRESSURE

International Journal of Modern Physics B ◽

10.1142/s0217979210056876 ◽

2010 ◽

Vol 24 (24) ◽

pp. 4851-4859

Author(s):

KAIHUA HE ◽

GUANG ZHENG ◽

GANG CHEN ◽

QILI CHEN ◽

MIAO WAN ◽

...

Keyword(s):

High Pressure ◽

Comparative Study ◽

Charge Density ◽

Band Gap ◽

Electronic Properties ◽

Cross Section ◽

First Principles ◽

First Principles Calculations ◽

Zinc Blende ◽

Structural And Electronic Properties

The structural and electronic properties of BN(5, 5) and C(5, 5) nanotubes under pressure are studied by using first principles calculations. In our study range, BN(5, 5) undergoes obvious elliptical distortion, while for C(5, 5) the cross section first becomes an ellipse and then, under further pressure, is flattened. The band gap of BN(5, 5) decreases with increasing pressure, which is inverse to that of zinc blende BN, whereas for C(5, 5) the metallicity is always preserved under high pressure. The population of charge density indicates that intertube bonding is formed under pressure. We also find that BN(5, 5) may collapse, and a new polymer material based on C(5, 5) is formed by applying pressure.

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Electronic Structure vs Phase in Al3V

MRS Proceedings ◽

10.1557/proc-141-141 ◽

1988 ◽

Vol 141 ◽

Author(s):

J.-H. Xu

Keyword(s):

Electronic Structure ◽

Bulk Modulus ◽

Total Energy ◽

Crystal Structures ◽

Lattice Constant ◽

Density Of States ◽

Phase Stability ◽

Local Density ◽

Young Modulus ◽

Good Agreement

AbstractThe electronic structure of Al3V vs its two different crystal structures (DO22 and Ll2) were investigated using local density total energy approach. The calculated results of the total energy showed that in Al3V the tetragonal DO22 phase is energetically favored as compared to the cubic Ll2 phase, the total energy in the former case is about 60 mRy/F.U. lower than that in the later case. The calculated lattice constant (a=3.72 Å, c=8.20 Å) is in fairly good agreement with experiment (a=3.778 Å, c=8.326 Å),and the bulk modulus (1.3 Mbar) is comparable with the experimental Young modulus (150 GPa) for Al3Ti. Furthermore, it is interesting to note that the density of states at EF in the tetragonal DO22 phase (0.14 states/eV-F.U.) is about one order magnitude smaller than that in the Ll2 phase (2.89 states/eV-F.U.). The electronic structure of Al3V seems to be fairly satisfactory in explaining its phase stability.

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Plane-wave pseudopotential study on mechanical and electronic properties for group III-V binary phases

MRS Proceedings ◽

10.1557/proc-743-l11.38 ◽

2002 ◽

Vol 743 ◽

Author(s):

S. Q. Wang ◽

H. Q. Ye

Keyword(s):

Bulk Modulus ◽

Electronic Properties ◽

Density Functional ◽

High Pressures ◽

Lattice Structure ◽

Structure Variation ◽

Group Iii ◽

Zinc Blende ◽

Structural And Electronic Properties ◽

Atom Configuration

ABSTRACTThe result of first-principles density functional calculations of the bulk modulus and related structural and electronic properties of the total 25 group III-V binary phases with zinc-blende and wurtzite structures are presented. The behavior of energy band structure variation under high pressures is also studied. It is found that the bulk modulus is more sensitive to the local atom configuration than the lattice structure. The crystallographic geometry plays an important role in the electronic property of these phases.

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Elastic and electronic properties of cubic cerium oxide under pressure via first principles

International Journal of Modern Physics B ◽

10.1142/s0217979214500702 ◽

2014 ◽

Vol 28 (14) ◽

pp. 1450070 ◽

Cited By ~ 1

Author(s):

Z. W. Niu ◽

B. Zhu ◽

Y. Cheng ◽

R. N. Song ◽

G. F. Ji

Keyword(s):

Electronic Properties ◽

Density Functional ◽

Local Density ◽

Lattice Parameters ◽

Total Density ◽

Functional Theory ◽

Young’S Moduli ◽

Shear Wave Velocities ◽

Total Density Of States ◽

Good Agreement

The elastic and electronic properties of cubic structure CeO 2 under pressure are investigated in the frame of density functional theory (DFT). By using the local-density approximation (LDA) plus U( LDA +U) method with U = 6 eV, the calculated lattice parameters, bulk modulus and elastic properties of the cubic CeO 2 at 0 GPa and 0 K are in good agreement with the available experimental data. The pressure dependences of lattice parameters, bulk and shear modulus, Debye temperature, Young's moduli, Poisson's ratio and the compressional and shear wave velocities of the cubic CeO 2 are obtained successfully. In addition, the total density of states (TDOS) and the band gaps of the cubic CeO 2 under pressures are also investigated. By comparing the results of LDA and LDA+U, both the conventional LDA and the LDA+U methods can be used to describe the structure of the cubic CeO 2 due to the electronic localization of 4f-electron in Ce which is not so strong. However, the LDA+U approach can obtain a proper shape of the density of electronic states that agrees well with the measured values.

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