Structural and elastic properties of TiN and AlN compounds: first-principles study

2014 ◽  
Vol 32 (2) ◽  
pp. 220-227 ◽  
Author(s):  
Meriem Fodil ◽  
Amine Mounir ◽  
Mohammed Ameri ◽  
Hadj Baltache ◽  
Bachir Bouhafs ◽  
...  
Keyword(s):  
Bulk Modulus ◽  
Elastic Properties ◽  
Rock Salt ◽  
Elastic Constants ◽  
First Principles ◽  
Density Functional ◽  
Theoretical Data ◽  
Generalized Gradient ◽  
Tin Compounds ◽  
Shear Moduli

AbstractFirst-principles calculations of the lattice constants, bulk modulus, pressure derivatives of the bulk modulus and elastic constants of AlN and TiN compounds in rock-salt (B1) and wurtzite (B4) structures are presented. We have used the fullpotential linearized augmented plane wave (FP-LAPW) method within the density functional theory (DFT) in the generalized gradient approximation (GGA) for the exchange-correlation functional. Moreover, the elastic properties of cubic TiN and hexagonal AlN, including elastic constants, bulk and shear moduli are determined and compared with previous experimental and theoretical data. Our results show that the structural transition at 0 K from wurtzite to rock-salt phase occurs at 10 GPa and −26 GPa for AlN and TiN, respectively. These results are consistent with those of other studies found in the literature.

Study of first principles on anisotropy and elastic constants of YAl3 compound

2020 ◽  
Vol 98 (4) ◽  
pp. 357-363
Author(s):  
Tahsin Özer
Keyword(s):  
Elastic Constants ◽  
First Principles ◽  
Density Functional ◽  
Theoretical Data ◽  
Anisotropic Behavior ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
The Density Functional Theory ◽  
Quantum Espresso

Using the density functional theory (DFT) calculations, the structural optimization of the YAl3 compound was performed on the generalized gradient approximation (GGA) with quantum ESPRESSO (QE) software. Elastic constants were calculated after the optimization process. Polycrystalline quantities, such as bulk and shear modulus, Young’s modulus, and Poisson’s ratio, were determined using calculated elastic constants. The anisotropy of the compound was studied in detail. As a result of the calculations made, it was observed that the YAl3 compound exhibited mechanically stable structure and anisotropic behavior. In the ht2-YAl3 phase, the effect of pressure on physical properties was investigated in detail. The obtained results were compared with the existing experimental and other theoretical data.

The structure, elastic and thermodynamic properties of Ti2GaC from first-principles calculation

2019 ◽  
Vol 33 (06) ◽  
pp. 1950030 ◽  
Author(s):  
Xiao-Xia Pu ◽  
Xiao-Jiang Long ◽  
Lin Zhang ◽  
Jun Zhu
Keyword(s):  
Thermodynamic Properties ◽  
Elastic Constant ◽  
Bulk Modulus ◽  
Elastic Constants ◽  
First Principles ◽  
Density Functional ◽  
Mechanical Stability ◽  
Theoretical Data ◽  
Debye Model ◽  
First Principles Calculation

In this work, the structure, elastic and thermodynamic properties of Ti2GaC at high pressure (P) and high-temperature (T) are studied based on the density functional first-principles. The lattice parameters and elastic constants are well consistent with some theoretical data and experimental results. The elastic constant of Ti2GaC increase monotonously with the increase of pressure (P), which demonstrates the mechanical stability of Ti2GaC at the pressure (P) from 0 to 200 GPa. Mechanical properties including Poisson’s ratio ([Formula: see text]), Young’s modulus (E), shear modulus (G) and bulk modulus (B), which are obtained from elastic constants C[Formula: see text]. The ratio B/G value shows that Ti2GaC is a brittle material, but its enhancing ductility significantly with the elevate of pressure (P). The Grüneisen parameters ([Formula: see text]), thermal expansion coefficient ([Formula: see text]), heat capacity (C[Formula: see text]), elastic constant (C[Formula: see text]), bulk modulus (B), energy (E) and volume (V) with the change of temperature (T) or pressure (P) are calculated within the quasi-harmonic Debye model for pressure (P) and temperatures (T) range in 1600 K and 100 GPa. Besides, densities of states and energy band are also obtained and analyzed in comparison with available theoretical data.

scholarly journals Structural, Electronic, Lattice Dynamic, and Elastic Properties of SnTiO3 and PbTiO3 Using Density Functional Theory

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Shiferaw Kuma ◽  
Menberu Mengesha Woldemariam
Keyword(s):  
Bulk Modulus ◽  
Elastic Properties ◽  
Density Of States ◽  
Elastic Constants ◽  
Density Functional ◽  
Phonon Dispersion ◽  
Electronic Band Structure ◽  
Theoretical Data ◽  
Modern Theory ◽  
Electronic Band

The structural, electronic, and elastic properties of tetragonal phase of SnTiO3 and PbTiO3 are investigated using first principle calculations. The unknown exchange-correlation functional is approximated with generalized gradient approximation (GGA) as implemented in pseudopotential plane wave approach. The convergence test of total energy with respect to energy cutoff and k-point sampling is preformed to ensure the accuracy of the calculations. The structural properties such as equilibrium lattice constant, equilibrium unit cell volume, bulk modulus, and its derivative are in reasonable agreement with the previous experimental and theoretical works. From elastic constants, mechanical parameters such as anisotropy factor A, shear modulus G, bulk modulus B, Young’s modulus E, and Poison’s ratio n are determined by using Voigt–Reuss–Hill average approximation. In addition, Debye temperature and longitudinal and transversal sound velocities are predicted from elastic constants. The electronic band structure and density of states of both compounds are obtained and compared with the available experimental as well as theoretical data. Born effective charge (BEC), phonon dispersion curve, and density of states are computed from functional perturbation theory (DFPT). Lastly, the spontaneous polarization is determined from the modern theory of polarization, and they are in agreement with the previous findings.

scholarly journals Pressure Effect on Elastic Constants and Related Properties of Ti3Al Intermetallic Compound: A First-Principles Study

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2015 ◽  
Author(s):  
Xianshi Zeng ◽  
Rufang Peng ◽  
Yanlin Yu ◽  
Zuofu Hu ◽  
Yufeng Wen ◽  
...  
Keyword(s):  
Intermetallic Compound ◽  
Debye Temperature ◽  
Elastic Constants ◽  
First Principles ◽  
Density Functional ◽  
Mechanical Stability ◽  
Theoretical Data ◽  
Young’S Moduli ◽  
Anisotropic Factor ◽  
Isotropic Pressure

Using first-principles calculations based on density functional theory, the elastic constants and some of the related physical quantities, such as the bulk, shear, and Young’s moduli, Poisson’s ratio, anisotropic factor, acoustic velocity, minimum thermal conductivity, and Debye temperature, are reported in this paper for the hexagonal intermetallic compound Ti 3 Al. The obtained results are well consistent with the available experimental and theoretical data. The effect of pressure on all studied parameters was investigated. By the mechanical stability criteria under isotropic pressure, it is predicted that the compound is mechanically unstable at pressures above 71.4 GPa. Its ductility, anisotropy, and Debye temperature are enhanced with pressure.

Structural, electronic and elastic properties of the B2-ScM (M =Au, Hg and Tl) intermetallic compounds: Ab initio calculations

2015 ◽  
Vol 04 (04) ◽  
pp. 1550020
Author(s):  
Ahmad A. Mousa ◽  
Jamil M. Khalifeh
Keyword(s):  
Mechanical Properties ◽  
Bulk Modulus ◽  
Intermetallic Compounds ◽  
Elastic Constants ◽  
Density Functional ◽  
Electronic Band Structure ◽  
Local Density ◽  
Full Potential ◽  
Generalized Gradient ◽  
Electronic Band

Structural, electronic, elastic and mechanical properties of ScM (M[Formula: see text][Formula: see text][Formula: see text]Au, Hg and Tl) intermetallic compounds are studied using the full potential-linearized augmented plane wave (FP-LAPW) method based on the density functional theory (DFT), within the generalized gradient approximation (GGA) and the local density approximation (LDA) to the exchange-correlation approximation energy as implemented in the Wien2k code. The ground state properties including lattice parameters, bulk modulus and elastic constants were all computed and compared with the available previous theoretical and experimental results. The lattice constant was found to increase in contrast to the bulk modulus which was found to decrease with every substitution of the cation (M) starting from Au till Tl in ScM. Both the electronic band structure and density-of-states (DOS) calculations show that these compounds possess metallic properties. The calculated elastic constants ([Formula: see text], [Formula: see text] and [Formula: see text] confirmed the elastic stability of the ScM compounds in the B2-phase. The mechanical properties and ductile behaviors of these compounds are also predicted based on the calculated elastic constants.

First-Principles Calculations of Elastic Properties of HoBi and ErBi

2013 ◽  
Vol 664 ◽  
pp. 672-676
Author(s):  
De Ming Han ◽  
Gang Zhang ◽  
Li Hui Zhao
Keyword(s):  
Shear Modulus ◽  
Physical Properties ◽  
Bulk Modulus ◽  
Elastic Properties ◽  
Lattice Constant ◽  
Elastic Constants ◽  
First Principles ◽  
Energy Band ◽  
First Principles Calculations ◽  
Future Work

We present first-principles investigations on the elastic properties of XBi (X=Ho, Er) compounds. Basic physical properties, such as lattice constant, elastic constants (Cij), isotropic shear modulus (G), bulk modulus (B), Young’s modulus (Y), Poisson’s ratio (υ), and Anisotropy factor (A) are calculated. The calculated energy band structures show that the two compounds possess semi-metallic character. We hope that these results would be useful for future work on two compounds.

Structural, Electronic and Elastic Properties of CeTl Intermetallic Compound

2016 ◽  
Vol 28 ◽  
pp. 1-4
Author(s):  
Deepika Shrivastava ◽  
Sankar P. Sanyal
Keyword(s):  
Bulk Modulus ◽  
Elastic Properties ◽  
Density Functional ◽  
Full Potential ◽  
Generalized Gradient ◽  
Pressure Derivative ◽  
Functional Theory ◽  
Augmented Plane Wave ◽  
Cscl Type ◽  
Linearized Augmented Plane Wave

The structural, electronic and elastic properties of CeTl with CsCl-type B2 structure have been investigated using full-potential linearized augmented plane wave (FP-LAPW) method based on density functional theory (DFT) within the generalized gradient approximation (GGA) for exchange and correlation potential. The ground state properties such as lattice constant, bulk modulus and pressure derivative of bulk modulus have been calculated which are in good agreement with available experimental data. The band structure and density of state depict that 4f electrons of Ce element have dominant character in electronic conduction and are responsible for metallic character of CeTl. The charge density plot reveals that the metallic as well as ionic bonding exist between Ce and Tl atoms. The calculated elastic constants indicate that CeTl is mechanically stable in cubic B2 phase and found to be ductile in nature.

First-principles study of structural, elastic and thermodynamic properties of AuIn2

2015 ◽  
Vol 29 (34) ◽  
pp. 1550222 ◽  
Author(s):  
Hai Ying Wu ◽  
Ya Hong Chen ◽  
Chen Rong Deng ◽  
Peng Fei Yin ◽  
Hong Cao
Keyword(s):  
Thermodynamic Properties ◽  
Bulk Modulus ◽  
Elastic Constants ◽  
First Principles ◽  
Pressure Effect ◽  
Structural Parameters ◽  
Text Structure ◽  
Generalized Gradient ◽  
Generalized Gradient Approximation ◽  
Theoretical Results

The structural, elastic and thermodynamic properties of [Formula: see text] in the [Formula: see text] structure under pressure have been investigated using ab initio plane wave pseudopotential method within the generalized gradient approximation. The calculated structural parameters and equation of state are in excellent agreement with the available experimental and theoretical results. The elastic constants of [Formula: see text] at ambient condition are calculated, and the bulk modulus obtained from these calculated elastic constants agrees well with the experimental data. The pressure dependence of the elastic constants, bulk modulus, shear modulus and Young’s modulus has also been investigated. The Debye temperature presents a slight increase with pressure. [Formula: see text] exhibits ductibility and low hardness characteristics, the ductibility increases while the hardness decreases with the increasing of pressure. The pressure effect on the heat capacity and thermal expansion coefficient for [Formula: see text] is much larger.

scholarly journals First Principles Study on the Structural, Elastic, Electronic and Optical Properties of Cubic ‘Half-Heusler’ Alloy RuVAs Under Pressure

2020 ◽  
pp. 51-63 ◽  
Keyword(s):  
Optical Properties ◽  
Band Structure ◽  
Bulk Modulus ◽  
Band Gap ◽  
Elastic Constants ◽  
First Principles ◽  
Theoretical Data ◽  
Lattice Parameter ◽  
Electronic Band ◽  
Electronic And Optical Properties

The pressure effect (0 to 40 GPa) on the structural, elastic, electronic, and optical properties of half-metallic compound RuVAs has been investigated employing the DFT based on the first-principles method. The CASTEP computer code is used for this investigation. The calculated lattice parameter show slide deviation from the synthesized and other theoretical data. The normalized lattice parameter and volume are decreased with increasing pressure. The zero pressure elastic constants and also the pressure-dependent elastic constants are positive up to 40 GPa and satisfy the Born stability condition which ensured that the compound RuVAs is stable in nature. At zero pressure, the electronic band gap of 0.159 eV is observed from the band structure calculations which ensured the semimetallic nature of RuVAs. No band gap is observed in the electronic band structure at 40 GPa which indicates the occurrence of phase transition of compound RuVAs at this pressure. We have calculated the value of bulk modulus B, shear modulus G, Young’s modulus E, Pugh ratio B/G, Poisson’s ratio ν and anisotropy factor A of this compound by using the Voigt-Reuss-Hill (VRH) averaging scheme under pressure. The bulk modulus shows a linear response to pressure so that the hardness of this material is increased with increasing pressure. Furthermore, the optical properties such as reflectivity, absorptivity, conductivity, dielectric constant, refractive index, and loss function of RuVAs were evaluated and discussed under pressure up to 40 GPa.

The structures, phase transition and elastic and thermodynamic properties of ZnS from first-principles calculations

2021 ◽  
pp. 2150143
Author(s):  
Bo Li ◽  
Weiyi Ren
Keyword(s):  
Phase Transition ◽  
Thermodynamic Properties ◽  
Bulk Modulus ◽  
First Principles ◽  
Density Functional ◽  
Mechanical Stability ◽  
Theoretical Data ◽  
Debye Model ◽  
Volume Curve ◽  
Temperature And Pressure

The phase transition of zinc sulfide (ZnS) from Zinc-blende (ZB) to a rocksalt (RS) structure and the elastic, thermodynamic properties of the two structures under high temperature and pressure are investigated by first-principles study based on the pseudo-potential plane-wave density functional theory (DFT) combined with the quasi-harmonic Debye model. The lattice constant [Formula: see text], bulk modulus [Formula: see text] and the pressure derivative of bulk modulus [Formula: see text]’ of the two structures are calculated. The results are in good agreement with experimental results and the other theoretical data. From the energy–volume curve, enthalpy equal principle and mechanical stability criterion, the transition pressures from the ZB to the RS structure are 16.83, 16.96 and 16.61 GPa, respectively. The three results and the experimental values 14.7–18.1, 16 GPa are very close to each other. Then the elastic properties are also calculated under the pressure ranging from 0 to 30 GPa. Finally, through the quasi-harmonic Debye model, the thermodynamic properties dependence of temperature and pressure in the ranges between 0–1600 K and 0–30 GPa are obtained successfully.

Sign in / Sign up

Export Citation Format

Share Document