Electronic structure and elastic properties of AgZn under pressure from first-principles calculations

In this study, the structural, elastic, electronic, and bonding nature of AgZn in B2 structure under pressure have been investigated by performing first principles calculations using density functional theory. The exchange-correlation potentials were treated within the generalized gradient approximation. The calculated quantities agree well with the available results. The electronic properties, such as band structure and density of states reveal that AgZn is metallic in nature with a large overlap at the Fermi level. The single-crystal elastic stiffness constants of AgZn are investigated using the stress–strain method. Present results for elastic constants show that AgZn is mechanically stable. The chemical bonding is interpreted by calculating the density of states and electron density distribution analysis. AgZn has ionic bonding characteristic.

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Electronic structure of cubic BaTbO3 from first-principles pseudopotential calculations

Canadian Journal of Physics ◽

10.1139/p06-008 ◽

2006 ◽

Vol 84 (2) ◽

pp. 115-120 ◽

Cited By ~ 3

Author(s):

G Y Gao ◽

K L Yao ◽

Z L Liu

Keyword(s):

Electronic Structure ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

Exchange Correlation ◽

Pseudopotential Calculations ◽

Correlation Potential ◽

Density Contour

First-principles calculations of the electronic structure are performed for cubic BaTbO3 using the plane-wave pseudopotential method within the framework of density functional theory and using the generalized gradient approximation for the exchange-correlation potential. Our calculations show that cubic BaTbO3 is metallic, and that this metallic character is mainly governed by the Tb 4f electrons and the hybridization between the Tb 5d and O 2p states. From the analysis of the density of states, band structure, and charge density contour, we find that the chemical bonding between Tb and O is covalent while that between Ba and TbO3 is ionic. PACS Nos.: 71.15.Mb, 71.20.-b

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Barrier to Migration of the Intrinsic Defects in Silicon in Different Charged System Using First-principles Calculations

MRS Proceedings ◽

10.1557/proc-864-e9.17 ◽

2005 ◽

Vol 864 ◽

Cited By ~ 1

Author(s):

Jinyu Zhang

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

Diffusion Behavior ◽

Generalized Gradient Approximation ◽

Charged System ◽

And Diffusion

AbstractUsing density functional theory (DFT) calculations within the generalized gradient approximation (GGA), we have investigated the structure, energies and diffusion behavior of Si defects including interstitial, vacancy, FFCD and divacancy in various charged states.

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Quantum-chemical study of nitrogen and magnesium co-doping in α-Cr2O3

Modern Physics Letters B ◽

10.1142/s0217984916502195 ◽

2016 ◽

Vol 30 (14) ◽

pp. 1650219

Author(s):

Soraya Jácome ◽

Arvids Stashans

Keyword(s):

First Principles ◽

Density Functional ◽

Quantum Chemical Study ◽

Chemical Study ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

Text Type ◽

Co Doping ◽

The Density Functional Theory

Study of corundum-type chromium oxide ([Formula: see text]-Cr2O3) crystal doped with the nitrogen and magnesium impurities has been carried out through the use of first-principles calculations based on the density functional theory (DFT) and generalized gradient approximation (GGA). Three cases corresponding different impurity–impurity distances have been considered. Structural, electronic and magnetic properties have been studied for all co-doping cases. The [Formula: see text]-type electrical conductivity was found when distance between the Mg and N atoms is equal to 4.10 Å. The results obtained are consistent with the available experimental data.

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THERMAL PROPERTIES OF THE XB2(X = Ag, Au) COMPOUNDS: A FIRST-PRINCIPLES STUDY

International Journal of Modern Physics B ◽

10.1142/s021797921350046x ◽

2013 ◽

Vol 27 (12) ◽

pp. 1350046

Author(s):

HAVVA BOGAZ OZISIK ◽

KEMAL COLAKOGLU ◽

ENGIN DELIGOZ

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

Debye Model ◽

First Principles Calculations ◽

Correlation Effects ◽

Generalized Gradient ◽

Functional Theory ◽

Exchange Correlation ◽

Generalized Gradient Approximation

The thermodynamic properties of AgB 2 and AuB 2 compounds in AlB 2 and OsB 2-type structures are investigated from first-principles calculations based on density functional theory (DFT) using projector augmented waves (PAW) potentials within the generalized gradient approximation (GGA) for modeling exchange-correlation effects, respectively. Specifically, using the quasi-harmonic Debye model, the effects of pressure and temperature, up to 100 GPa and 1400 K, on the bulk modulus, Debye temperature, thermal expansion, heat capacity and the Grüneisen parameter are calculated successfully and trends are discussed.

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Electronic, Optical and Vibrational Properties of B3N3H6 from First-Principles Calculations

10.21203/rs.3.rs-467643/v1 ◽

2021 ◽

Author(s):

Yun-Dan Gan ◽

Han Qin ◽

Fu-Sheng Liu ◽

Zheng-Tang Liu ◽

Cheng lu Jiang ◽

...

Keyword(s):

First Principles ◽

Density Functional ◽

Local Density ◽

Structural Parameters ◽

Vibrational Properties ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

Conductivity Loss ◽

Good Agreement

Abstract The electronic, optical and vibrational properties of B3N3H6 have been calculated by means of first-principles density functional theory (DFT) calculations within the generalized gradient approximation (GGA) and the local density approximation (LDA). The calculated structural parameters of B3N3H6 are in good agreement with experimental work. With the band structure and density of states (DOS), we have analyzed the optical properties including the complex dielectric function, refractive index, absorption, conductivity, loss function and reflectivity. By the contrast, it is found that on the (001) component and (100) component have obvious optical anisotropy. Moreover, the vibrational properties have been obtained and analyzed.

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First-Principles Calculations of the Structure and Magnetic Phases of FeAs2 Compound under Pressure

SPIN ◽

10.1142/s2010324718500169 ◽

2018 ◽

Vol 08 (04) ◽

pp. 1850016 ◽

Cited By ~ 1

Author(s):

O. Sebaa ◽

Y. Zaoui ◽

K. O. Obodo ◽

H. Bendaoud ◽

L. Beldi ◽

...

Keyword(s):

Phase Transition ◽

First Principles ◽

Density Functional ◽

Stable Phase ◽

Spin Orbit Coupling ◽

First Principles Calculations ◽

Generalized Gradient ◽

Electronic Density ◽

Functional Theory ◽

Spin Ordering

Understanding of different magnetic configurations for the FeAs2 iron pnictide compound is carried out using first-principles studies based on spin density functional theory (DFT) within the generalized gradient approximation (GGA), including the spin–orbit coupling (SOC). The calculated stable phase is in the marcasite (Pnnm) with nonmagnetic spin-ordering. We find that the FeAs2 compound in the nonmagnetic (NM) marcasite phase undergoes pressure-induced phase transition to the antiferromagnetic (AFM1) marcasite phase at 12[Formula: see text]GPa, then to the AFM CuAl2 ([Formula: see text]4/mcm) phase at 63[Formula: see text]GPa. The phase transition is also accompanied by semiconducting (marcasite phase) to metallic (CuAl2 phase) transition. The calculated electronic density of states profile shows the hybridization of the Fe-3[Formula: see text] and As-4[Formula: see text] orbitals plays an important role in determining the electronic and magnetic characters of this compound. The associated phase transition results in increased Fe-3d orbitals around the Fermi energy level.

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First-Principles Calculations of the Electronic Structure and Optical Properties of Yttrium-Doped ZnO Monolayer with Vacancy

Materials ◽

10.3390/ma13030724 ◽

2020 ◽

Vol 13 (3) ◽

pp. 724

Author(s):

Qian Wu ◽

Ping Wang ◽

Yan Liu ◽

Han Yang ◽

Jingsi Cheng ◽

...

Keyword(s):

Oxygen Vacancy ◽

First Principles ◽

Density Functional ◽

Density Functional Theory Calculations ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

Light Region ◽

Application Potential ◽

Doped Zno

The electronic structures and optical characteristics of yttrium (Y)-doped ZnO monolayers (MLs) with vacancy (zinc vacancy, oxygen vacancy) were investigated by the first-principles density functional theory. Calculations were performed with the GGA+U (generalized gradient approximation plus U) approach, which can accurately estimate the energy of strong correlation semiconductors. The results show that the formation energy values of Y-doped ZnO MLs with zinc or oxygen vacancy (VZn, VO) are positive, implying that the systems are unstable. The bandgap of Y-VZn-ZnO was 3.23 eV, whereas that of Y-VO-ZnO was 2.24 eV, which are smaller than the bandgaps of pure ZnO ML and Y-doped ZnO MLs with or without VO. Impurity levels appeared in the forbidden band of ZnO MLs with Y and vacancy. Furthermore, Y-VZn-ZnO will result in a red-shift of the absorption edge. Compared with the pure ZnO ML, ZnO MLs with one defect (Y, VZn or VO), and Y-VZn-ZnO, the absorption coefficient of Y-VO-ZnO was significantly enhanced in the visible light region. These findings demonstrate that Y-VO-ZnO would have great application potential in photocatalysis.

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DFT calculations of tin dioxide crystals containing heavily-doped fluorine

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633614500692 ◽

2014 ◽

Vol 13 (08) ◽

pp. 1450069 ◽

Cited By ~ 2

Author(s):

Freddy Marcillo ◽

Arvids Stashans

Keyword(s):

First Principles ◽

Density Functional ◽

Tin Dioxide ◽

Empirical Studies ◽

Experimental Fact ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

The Density Functional Theory ◽

Heavily Doped

First-principles calculations based on the density functional theory (DFT) within the generalized gradient approximation have been used in the present research. Fluorine doping in the SnO 2 crystals has been carried out considering a number of different defect concentrations. Dopant influence upon structural, electronic and electrical properties of the tin dioxide has been discussed in detail. The system presents n-type electrical conductivity relating our work directly to a number of empirical studies in this area. An experimental fact that n-type conductivity tends to decrease at rather high fluorine impurity rates has been explained at the theoretical level.

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First-Principles Calculations on Pure and Ga-Doped Anatase TiO2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.156-157.1385 ◽

2010 ◽

Vol 156-157 ◽

pp. 1385-1388

Author(s):

Rui Qing Xu ◽

Lan Fang Yao ◽

Lin Li ◽

Shuo Wang ◽

Lin Lin Tian ◽

...

Keyword(s):

Band Gap ◽

First Principles ◽

Density Functional ◽

Correlation Energy ◽

Anatase Tio2 ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

The Density Functional Theory ◽

Band Gap Narrowing

First-principles calculations using the plane-wave pseudo-potential (PWPP) method based on the density functional theory (DFT) is employed to study the crystal structure, band gap, density of states of anatase TiO2 doped with gadolinium (Gd). The generalized gradient approximation (GGA) based on exchange-correlation energy optimization is employed to calculate them. The calculated results demonstrate that the mixing of gadolinium dopants induces states with original titanium 3d and oxygen 2p valence band attributes to the band gap narrowing. This can enhance the photocatalytic activity of anatase TiO2.

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First-Principles Study of the Structural Stability and Electronic and Elastic Properties of Helium inα-Zirconium

Advances in Condensed Matter Physics ◽

10.1155/2014/929750 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 7

Author(s):

Jian Zheng ◽

Huijun Zhang ◽

Xiaosong Zhou ◽

Jianhua Liang ◽

Liusi Sheng ◽

...

Keyword(s):

Density Functional Theory ◽

Elastic Properties ◽

Density Of States ◽

First Principles ◽

Octahedral Site ◽

Density Functional ◽

Formation Energy ◽

Interstitial Site ◽

First Principles Calculations ◽

Functional Theory

First-principles calculations within density functional theory have been performed to investigate the behaviors of helium inα-zirconium. The most favorable interstitial site for He inα-Zr is not an ordinary tetrahedral or octahedral site, but a basal octahedral site with a formation energy as low as 2.40 eV. The formation energy reduces to 1.25 eV in the presence of preexisting vacancies. The analysis on the density of states and the charge density has been carried out. In addition, the influences of He and small He-V complexes on the elastic properties have been studied. The He-V complexes have been found to greatly affect the elastic properties compared with He alone.

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