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

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.

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Stability and the Electronic Structure of XB2 (X = Pt, Ir, Pd, Rh, Os) Diborides

Latvian Journal of Physics and Technical Sciences ◽

10.1515/lpts-2017-0026 ◽

2017 ◽

Vol 54 (4) ◽

pp. 49-57

Author(s):

A.I. Popoola ◽

A.Y. Odusote ◽

O.E. Ayo-Ojo

Keyword(s):

Electronic Structure ◽

Density Of States ◽

Platinum Group Metal ◽

First Principle ◽

Boron Addition ◽

Superhard Materials ◽

Electronic Density ◽

First Principle Calculations ◽

Structural And Electronic Properties ◽

Metal Diborides

AbstractFirst-principle calculations have been performed to investigate the structural and electronic properties of platinum group metal diborides in the stoichiometry XB2(X = Pt, Ir, Pd, Rh, Os). All investigated compounds have shown to belong to the orthorhombicPmmn space group rather than theC2/m previously predicted in some of the compositions. Compressibility will reduce with boron addition in Pt, Pd and Rh, but will increase with boron addition into Ir and Os. The electronic density of states show that all the compounds are metals, with PtB2, PdB2and OsB2being potentially incompressible and superhard materials.

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AB INITIO CALCULATION OF THE ELECTRONIC AND MECHANICAL PROPERTIES OF TRANSITION METALS AND THEIR NITRIDES

Modern Physics Letters B ◽

10.1142/s0217984904006895 ◽

2004 ◽

Vol 18 (07n08) ◽

pp. 281-289 ◽

Cited By ~ 12

Author(s):

CHENG-BIN LI ◽

MING-KAI LI ◽

FU-QING LIU ◽

XIANG-JUN FAN

Keyword(s):

Mechanical Properties ◽

Transition Metals ◽

Ab Initio Calculations ◽

Charge Density ◽

Ab Initio ◽

Electronic Properties ◽

Density Of States ◽

Ab Initio Calculation ◽

Structural And Electronic Properties

The results of ab initio calculations of the bulk moduli (B0) and related structural and electronic properties of selected transition metals and their nitrides are presented. There is a correlation between B0 and valence charge density. B0 does not vary monotonically with the addition of d electrons. Charge density and density of states (DOS) plots enable us to explain it.

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Theoretical Studies of Oxygen Vacancies in YBa2Cu3O7-y

MRS Proceedings ◽

10.1557/proc-99-463 ◽

1987 ◽

Vol 99 ◽

Author(s):

Brent A. Richert ◽

Roland E. Allen

Keyword(s):

Electronic Structure ◽

Density Of States ◽

Fermi Energy ◽

Oxygen Vacancies ◽

Tight Binding ◽

Theoretical Studies ◽

Metal Atoms

ABSTRACTWe have performed semiempirical tight-binding calculations of the electronic structure of YBa2Cu3O7, with dand s orbitals included for all the metal atoms and p and sorbitals for oxygen. Here we report studies of oxygen vacancies on the O(1) chain sites in YBa2Cu3O7-y. The modification of the density of states ρ(E) and the shift of the Fermi energy Ep were calculated for 0 < y ≤ 1.0. The Fermi energy is found to increase monotonically with y, confirming the expectation that oxygen vacancies act as donors. Also, ρ(EF)is found to decrease with y.

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The impact of anionic vacancies on the mechanical properties of NbC and NbN: An ab initio study

Computational Materials Science ◽

10.1016/j.commatsci.2021.111113 ◽

2022 ◽

Vol 203 ◽

pp. 111113

Author(s):

P.W. Muchiri ◽

K.K. Korir ◽

N.W. Makau ◽

G.O. Amolo

Keyword(s):

Mechanical Properties ◽

Ab Initio ◽

Ab Initio Study ◽

The Impact

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

Volume 1: Plant Operations, Maintenance, Engineering, Modifications, Life Cycle and Balance of Plant; Nuclear Fuel and Materials; Radiation Protection and Nuclear Technology Applications ◽

10.1115/icone21-15407 ◽

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.

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

Materials ◽

10.3390/ma12060967 ◽

2019 ◽

Vol 12 (6) ◽

pp. 967 ◽

Cited By ~ 5

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.

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