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

Using the First principles calculations, the crystal structure, band gap, total and partial density of states (DOS) of anatase TiO2and anatase TiO2doped with Yttrium were calculated by a plane-wave pseudopotential (PWPP) method based on density functional theory (DFT). The generalized gradient approximation (GGA) based on exchange-correlation energy optimization was employed to calculate them. From the calculation results, the band gap of anatase TiO2and Y3+doped TiO2are about 2.15eV and 0.86eV. The calculated results demonstrated that the mixing of Yttrium (Y) 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 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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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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First-Principle Study of Effect of Strain on the Band Structure of Germanane Monolayer

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.787.25 ◽

2018 ◽

Vol 787 ◽

pp. 25-30

Author(s):

Lei Liu ◽

Yan Ju Ji ◽

Yi Fan Liu

Keyword(s):

Band Structure ◽

Band Gap ◽

First Principles ◽

Density Functional ◽

Catalytic Properties ◽

Significant Implication ◽

First Principle ◽

First Principles Calculations ◽

Biaxial Strain ◽

Functional Theory

The effect of strain on the band structure of the GeH monolayer has been investigated by first-principles calculations based on density functional theory. The results show that the change of the band gap under the zigzag strain, the armchair strain and the biaxial strain is nonlinear. The effect of the biaxial strain on the band gap is the most obvious. In addition, the changes of energy under the three kinds of strain are asymmetric and the biaxial strain make the energy change the most. This work has significant implication of strain to tune optical catalytic properties of GeH monolayer.

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

Canadian Journal of Physics ◽

10.1139/cjp-2015-0684 ◽

2016 ◽

Vol 94 (3) ◽

pp. 328-333

Author(s):

Yasemin Ö. Çiftci

Keyword(s):

Density Of States ◽

First Principles ◽

Density Functional ◽

Elastic Stiffness ◽

Distribution Analysis ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

B2 Structure ◽

Bonding Characteristic

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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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 structure and magnetic ordering in gadolinium-doped AlGaN from LSDA + U calculations

International Journal of Computational Materials Science and Engineering ◽

10.1142/s2047684118500197 ◽

2018 ◽

Vol 07 (03) ◽

pp. 1850019 ◽

Cited By ~ 2

Author(s):

S. Belhachi ◽

S. Amari ◽

B. Bouhafs

Keyword(s):

Density Functional Theory ◽

Magnetic Properties ◽

Band Gap ◽

First Principles ◽

Density Functional ◽

Magnetic Ordering ◽

First Principles Calculations ◽

Functional Theory ◽

The Density Functional Theory ◽

Indirect Band Gap

We present first-principles calculations of the structural, electronic and magnetic properties of Gd-doped [Formula: see text] based on the density functional theory within [Formula: see text] schemes. It is found that Gd atom favors substituting for Al site. Compared with undoped [Formula: see text], the Gd-doped [Formula: see text] has become an indirect band gap semiconductor of reduced band gap. The magnetic moment [Formula: see text] per molecule mainly comes from Gd ion with little contribution from the Ga, Al and N atoms. It is confirmed that the ferromagnetic configuration is stable for [Formula: see text]. It is found also that there is hybridization between the forbital of the Gd atom and the [Formula: see text] orbital of the N atom.

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FIRST-PRINCIPLES CALCULATIONS ON ELECTRONIC STRUCTURES OF TiO2 ANATASE (101) SURFACES WITH N IMPURITIES

Modern Physics Letters B ◽

10.1142/s0217984911025535 ◽

2011 ◽

Vol 25 (02) ◽

pp. 119-129 ◽

Cited By ~ 4

Author(s):

QI LI CHEN ◽

GUANG ZHENG ◽

KAI HUA HE ◽

BO LI

Keyword(s):

Band Gap ◽

Electronic Structures ◽

Density Functional ◽

First Principles Calculations ◽

Functional Theory ◽

Tio2 Anatase ◽

Exchange Correlation ◽

N Doping ◽

Band Gap Narrowing ◽

Coefficient Method

The electronic structures of nitrogen ( N )-doped TiO 2 anatase (101) surfaces have been investigated by density functional theory (DFT) plane-wave pseudopotential method with general gradient approximation (GGA) + U (Hubbard coefficient) method being adopted to describe the exchange-correlation effects. Both substitutional and interstitial N doping have been considered in this paper as well as the case of surface N adsorption. The results demonstrated that there is no obvious band gap narrowing observed by introducing N impurities except several N 2p states lying in the gap, whereas the introduction of oxygen vacancy was confirmed playing an important role on band gap narrowing. The results accord well with some experimental results.

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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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