Intrinsic Brittlement of Mo3Si by First-Principle Calculations

First-principles method has been used to study the intrinsic brittlement of Mo3Si. The crystal constants, formation energy, cohesive energy, electronic structure, elastic constants of Mo3Si were calculated. The results were in good agreement with experiment data. Electronic structures showed that the strong covalent bonding between the nearest neighbour Mo atoms, which arrange perpendicularly each other, leads to embrittlement of Mo3Si.

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First Principle Calculations for Silver Halides AgBr, AgCl, and AgF

ARO-The Scientific Journal of Koya University ◽

10.14500/aro.10874 ◽

2021 ◽

Vol 9 (2) ◽

pp. 71-75

Author(s):

Akram H. Taha

Keyword(s):

Electronic Structures ◽

Density Functional ◽

Total Density ◽

First Principle ◽

Silver Halides ◽

Functional Theory ◽

First Principle Calculations ◽

Almost All ◽

Total Density Of States ◽

Good Agreement

Density functional theory (DFT) coupled with ) method are carried out to calculate the electronic structures of AgX (X; Br, Cl, and F). The effect of hybridizing between 4d orbital of Ag element and the p orbitals of the X in the valence band plays a very important role in the total density of states configuration. The electronic structure has been studied and all results were compared with the experimental and theoretical values. The importance of this work is that there is insufficient studies of silver halides corresponding the great importance of these compounds. Almost all the results were consistent with the previous studies mentioned here. We found the band gap of AgX to be 2.343 eV, 2.553 eV, and 1.677 eV for AgBr, AgCl, and AgF respectively which are in good agreement with the experimental results.

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Structural and electronic properties of InPBi alloys

Modern Physics Letters B ◽

10.1142/s0217984914501401 ◽

2014 ◽

Vol 28 (17) ◽

pp. 1450140 ◽

Cited By ~ 2

Author(s):

Xianlong Zhang ◽

Pengfei Lu ◽

Lihong Han ◽

Zhongyuan Yu ◽

Jun Chen ◽

...

Keyword(s):

Fermi Level ◽

Electronic Properties ◽

Formation Energy ◽

Covalent Bonding ◽

First Principle ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Biaxial Strain ◽

First Principle Calculations ◽

Structural And Electronic Properties

First-principle calculations have been performed to systematically investigate structural and electronic properties of InPBi alloys. The formation energy of seven different configurations is studied. The strength of covalent bonding largely depends on the strong s–p hybridization among In -5s, P -3p and Bi -6p states. The band gap of InPBi shrinks clearly with the increasing Bi concentration and the band edge shifts when spin-orbit coupling (SOC) is considered. The insertion of Bi atom leads to hybridization of In / P / Bi p states which contributes a lot around Fermi level. In addition, our results show that the biaxial strain is an effective method to tune the electronic properties of the system.

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The thermal stability of FAPbBr3 nanocrystals from temperature-dependent photoluminescence and first-principles calculations

RSC Advances ◽

10.1039/d0ra07668f ◽

2020 ◽

Vol 10 (72) ◽

pp. 44373-44381

Author(s):

Xiaozhe Wang ◽

Qi Wang ◽

Zhijun Chai ◽

Wenzhi Wu

Keyword(s):

First Principles ◽

First Principle ◽

First Principles Calculations ◽

Temperature Dependent ◽

Time Resolved ◽

First Principle Calculations ◽

Steady State Time ◽

Time Resolved Photoluminescence ◽

Thermal Stability Of ◽

Temperature Dependent Photoluminescence

The thermal properties of FAPbBr3 perovskite nanocrystals (PNCs) is investigated by use of temperature-dependent steady-state/time-resolved photoluminescence and first-principle calculations.

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Accelerated materials design of Na0.5Bi0.5TiO3 oxygen ionic conductors based on first principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/c5cp02181b ◽

2015 ◽

Vol 17 (27) ◽

pp. 18035-18044 ◽

Cited By ~ 63

Author(s):

Xingfeng He ◽

Yifei Mo

Keyword(s):

First Principles ◽

Materials Design ◽

First Principle ◽

First Principles Calculations ◽

Ionic Conductors ◽

First Principle Calculations

First principle calculations are performed to accelerate the design of new oxygen ionic conductors.

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Surface Stoichiometry and Oxidation of NiTi

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.307.387 ◽

2013 ◽

Vol 307 ◽

pp. 387-390

Author(s):

Jian Xin Zhu ◽

Da Wei Jin ◽

Jian Zhang ◽

Hong Liang Zhao

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

First Principles ◽

Electronic Structures ◽

Formation Energy ◽

Population Analysis ◽

Niti Shape Memory Alloy ◽

Wave Method ◽

Plane Wave Method ◽

Oxygen Atoms

NiTi shape memory alloy is considered to be the most important shape memory alloys for its salient superelasticity and shape memory effect,which are displayed in martensitic transformations.In this paper, first-principles plane-wave method is utilized to systemically investigate the geometrical and electronic structures of NiTi (100) surface.Calculated the adsorption of oxygen atoms on the Ti/ NITI different location .The formation energy, Millikan population analysis results show that the Oxygen atoms easy to be adsorbed on the surface of Ti end surface,formation of TiO2.

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Spin Gapless Semiconductor–Nonmagnetic Semiconductor Transitions in Fe-Doped Ti2CoSi: First-Principle Calculations

Applied Sciences ◽

10.3390/app8112200 ◽

2018 ◽

Vol 8 (11) ◽

pp. 2200 ◽

Cited By ~ 3

Author(s):

Yu Feng ◽

Zhou Cui ◽

Ming-sheng Wei ◽

Bo Wu ◽

Sikander Azam

Keyword(s):

Magnetic Moment ◽

Electronic Structures ◽

Magnetic Moments ◽

Total Magnetic Moment ◽

First Principle ◽

Half Metallic ◽

Heusler Compound ◽

First Principle Calculations ◽

Metallic Ferromagnet

Employing first-principle calculations, we investigated the influence of the impurity, Fe atom, on magnetism and electronic structures of Heusler compound Ti2CoSi, which is a spin gapless semiconductor (SGS). When the impurity, Fe atom, intervened, Ti2CoSi lost its SGS property. As TiA atoms (which locate at (0, 0, 0) site) are completely occupied by Fe, the compound converts to half-metallic ferromagnet (HMF) TiFeCoSi. During this SGS→HMF transition, the total magnetic moment linearly decreases as Fe concentration increases, following the Slate–Pauling rule well. When all Co atoms are substituted by Fe, the compound converts to nonmagnetic semiconductor Fe2TiSi. During this HMF→nonmagnetic semiconductor transition, when Fe concentration y ranges from y = 0.125 to y = 0.625, the magnetic moment of Fe atom is positive and linearly decreases, while those of impurity Fe and TiB (which locate at (0.25, 0.25, 0.25) site) are negative and linearly increase. When the impurity Fe concentration reaches up to y = 1, the magnetic moments of Ti, Fe, and Si return to zero, and the compound is a nonmagnetic semiconductor.

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P-Cu alloy as anode materials for lithium ion batteries: a first-principles study

E3S Web of Conferences ◽

10.1051/e3sconf/202124503003 ◽

2021 ◽

Vol 245 ◽

pp. 03003

Author(s):

Zhaowen Huang ◽

Benjing Chen ◽

Jingyang Li ◽

Lingzhi Zhao

Keyword(s):

Expansion Coefficient ◽

First Principles ◽

Volume Expansion ◽

Anode Materials ◽

Formation Energy ◽

Lithium Ion ◽

Lithium Intercalation ◽

First Principle ◽

Cu Alloy ◽

Volume Expansion Coefficient

In this paper, based on the first principle method, the mechanism of lithium intercalation and deintercalation of P-Cu alloy as anode material of lithium-ion battery was studied. The results followed that the volume expansion coefficient of Li-P-Cu is small, 59.4650% for Li2PCu3 and 61.4071% for Li2P2Cu, indicating that the introduction of Cu can effectively inhibit the volume expansion of phosphorus. And PCu3 is superior to P2Cu in terms of volume expansion coefficient and lithium intercalation formation energy and good conductivity.

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Structural, electronic and elastic properties of Ti2TlC, Zr2TlC and Hf2TlC

Open Physics ◽

10.2478/s11534-009-0022-z ◽

2009 ◽

Vol 7 (4) ◽

Cited By ~ 1

Author(s):

Abdelmadjid Bouhemadou

Keyword(s):

Elastic Properties ◽

Finite Strain ◽

High Pressures ◽

Applied Pressure ◽

First Principle ◽

Shear Moduli ◽

Lattice Constants ◽

First Principle Calculations ◽

Electrical Conductors ◽

Good Agreement

AbstractUsing First-principle calculations, we have studied the structural, electronic and elastic properties of M2TlC, with M = Ti, Zr and Hf. Geometrical optimization of the unit cell is in good agreement with the available experimental data. The effect of high pressures, up to 20 GPa, on the lattice constants shows that the contractions are higher along the c-axis than along the a axis. We have observed a quadratic dependence of the lattice parameters versus the applied pressure. The band structures show that all three materials are electrical conductors. The analysis of the site and momentum projected densities shows that bonding is due to M d-C p and M d-Tl p hybridizations. The M d-C p bonds are lower in energy and stiffer than M d-Tl p bonds. The elastic constants are calculated using the static finite strain technique. We derived the bulk and shear moduli, Young’s modulus and Poisson’s ratio for ideal polycrystalline M2TlC aggregates. We estimated the Debye temperature of M2TlC from the average sound velocity. This is the first quantitative theoretical prediction of the elastic properties of Ti2TlC, Zr2TlC, and Hf2TlC compounds that requires experimental confirmation.

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