scholarly journals Influence of Isostatic Pressure on the Elastic and Electronic Properties of K2SiF6:Mn4+

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 613
Author(s):  
Mekhrdod Subhoni ◽  
Umar Zafari ◽  
Chong-Geng Ma ◽  
Alok M. Srivastava ◽  
William W. Beers ◽  
...  
Keyword(s):  
Electronic Properties ◽  
Elastic Constants ◽  
Density Functional ◽  
Pressure Effects ◽  
First Principles Calculations ◽  
Functional Theory ◽  
Crystal Field Strength ◽  
Equation Of States ◽  
Strain Relationship ◽  
The Relationship

Isostatic pressure effects on the elastic and electronic properties of non-doped and Mn4+-doped K2SiF6 (KSF) have been investigated by first-principles calculations within density functional theory (DFT). Bulk modulus was obtained by the Murnaghan’s equation of states (EOS) using the relationship between volume and pressures at pressures between 0 and 40 GPa, and elastic constants were calculated by the stress–strain relationship giving small distortions at each pressure point. The other elastic parameters such as shear modulus, sound velocity and Debye temperature, which can be obtained from the elastic constants, were also estimated. The influence of external isostatic pressure on the electronic properties, such as crystal field strength 10Dq and emission energy of 2E → 4A2 transition (Eem), of KSF:Mn4+ was also studied. The results suggest that 10Dq and Eem linearly increase and decrease, respectively, with increasing pressure.

scholarly journals Effect of Defects on Spontaneous Polarization in Pure and Doped LiNbO3: First-Principles Calculations

Materials ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 100 ◽  
Author(s):  
Weiwei Wang ◽  
Dahuai Zheng ◽  
Mengyuan Hu ◽  
Shahzad Saeed ◽  
Hongde Liu ◽  
...  
Keyword(s):  
Spontaneous Polarization ◽  
First Principles ◽  
Density Functional ◽  
Lattice Distortion ◽  
Stable Structure ◽  
First Principles Calculations ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Specific Configuration ◽  
The Relationship

Numerous studies have indicated that intrinsic defects in lithium niobate (LN) dominate its physical properties. In an Nb-rich environment, the structure that consists of a niobium anti-site with four lithium vacancies is considered the most stable structure. Based on the density functional theory (DFT), the specific configuration of the four lithium vacancies of LN were explored. The results indicated the most stable structure consisted of two lithium vacancies as the first neighbors and the other two as the second nearest neighbors of Nb anti-site in pure LN, and a similar stable structure was found in the doped LN. We found that the defects dipole moment has no direct contribution to the crystal polarization. Spontaneous polarization is more likely due to the lattice distortion of the crystal. This was verified in the defects structure of Mg2+, Sc3+, and Zr4+ doped LN. The conclusion provides a new understanding about the relationship between defect clusters and crystal polarization.

scholarly journals Carrier-mediated ferromagnetism in two-dimensional PtS2

RSC Advances ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 952-957 ◽  
Author(s):  
Konstantina Iordanidou ◽  
Michel Houssa ◽  
Clas Persson
Keyword(s):  
Density Functional Theory ◽  
Electronic Properties ◽  
First Principles ◽  
Density Functional ◽  
Hole Doping ◽  
Two Dimensional ◽  
First Principles Calculations ◽  
Functional Theory ◽  
The Impact

Using first principles calculations based on density functional theory the impact of hole doping on the magnetic and electronic properties of two dimensional PtS2 is studied.

scholarly journals Elastic Properties and Electronic Properties of MxNy (M = Ti, Zr) from First Principles Calculations

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1640 ◽  
Author(s):  
Yangqi Ji ◽  
Xiaoli Yuan
Keyword(s):  
Electronic Properties ◽  
Elastic Properties ◽  
First Principles ◽  
Density Functional ◽  
Mechanical Stability ◽  
Central Force ◽  
First Principles Calculations ◽  
Functional Theory ◽  
Space Group ◽  
Group I

The elastic properties and electronic properties of MxNy (M = Ti, Zr) TiN, Ti2N, Zr3N4, ZrN with different structures have been investigated using density functional theory. Through the calculation of the elastic constants, it was found that all of these structures meet the mechanical stability except for ZrN with space group P63mc. Their mechanical properties are studied by a comparison of various parameters. The stiffness of TiN is larger than that of ZrN with space group Fm 3 ¯ m. Ti2N’s stiffness with space group I41/amdz is larger than Ti2N with space group P42/mnm. Zr3N4’s stiffness with space group Pnam is largest in three structures of Zr3N4. TiN, Ti2N and ZrN are non-central force, Zr3N4 is central force. TiN and ZrN with space group Fm 3 ¯ m are brittle, and TiN is brittler than ZrN with space group Fm 3 ¯ m. The two kinds of Ti2N are brittle and Ti2N with space group I41/amdz is larger. Three structures of Zr3N4 are tough and Zr3N4 with space group I 4 ¯ 3d is the toughest. Meanwhile, the electronic properties of TiN, Ti2N, Zr3N4 and ZrN were calculated, possible superconducting properties of the studied materials were predicted.

scholarly journals Hydrogenated derivatives of hexacoordinated metallic Cu2Si monolayer

RSC Advances ◽  
2018 ◽  
Vol 8 (70) ◽  
pp. 39976-39982 ◽  
Author(s):  
E. Unsal ◽  
F. Iyikanat ◽  
H. Sahin ◽  
R. T. Senger
Keyword(s):  
Density Functional Theory ◽  
Electronic Properties ◽  
Surface Functionalization ◽  
First Principles ◽  
Density Functional ◽  
First Principles Calculations ◽  
Hydrogen Atoms ◽  
Functional Theory ◽  
Derivatives Of

Herein, we carried out first-principles calculations based on density functional theory to investigate the effects of surface functionalization with hydrogen atoms on structural, dynamical and electronic properties of Cu2Si monolayer.

STRUCTURAL, ELASTIC AND ELECTRONIC PROPERTIES OF OXYGEN SUBSTITUTION IN CUBIC Zr3N4 AND Ti3N4

2013 ◽  
Vol 27 (18) ◽  
pp. 1350095 ◽  
Author(s):  
YI-MING CHEN ◽  
WEI CHENG ◽  
BIN LIAO ◽  
XU ZHANG
Keyword(s):  
Fermi Level ◽  
Electronic Properties ◽  
Density Functional ◽  
First Principles Calculations ◽  
Functional Theory ◽  
Shear Moduli ◽  
Young’S Moduli ◽  
The Density Functional Theory ◽  
Oxygen Substitution ◽  
Nitrogen Bond

The structural, elastic and electronic properties of O-doped and un-doped cubic Zr 3 N 4 and Ti 3 N 4 are studied by first principles calculations based on the density functional theory. The bulk and shear moduli, as well as Young's moduli, decrease after doping with oxygen, which is due to the lengthening of the metal-nitrogen bond as well as the inflation of the cell volume. The changes in elastic properties are consistent with available experimental results. Both nitrides change from brittle to ductile when doped with oxygen, and all materials can be regarded as being elastic isotropic. The band structure and density of states are calculated to discuss the electronic properties of O-doped cubic Zr 3 N 4 and Ti 3 N 4, the presence of oxygen has significant influence on the electronic structure near the Fermi level. The gap at Fermi level is vanished which confirms the metallic character when O is introduced into nitrides. It means that doping with oxygen will have important effects on the optical properties of Zr and Ti nitrides.

scholarly journals Me-graphane: tailoring the structural and electronic properties of Me-graphene via hydrogenation

2021 ◽  
Author(s):  
Enesio Marinho Jr ◽  
Pedro Alves da Silva Autreto
Keyword(s):  
Density Functional Theory ◽  
Electronic Properties ◽  
First Principles ◽  
Density Functional ◽  
Large Family ◽  
First Principles Calculations ◽  
Functional Theory ◽  
Structural And Electronic Properties ◽  
Potential Applications

Graphene-based materials (GBMs) are a large family of materials that have attracted great interest due to potential applications. In this work, we applied first-principles calculations based on density functional theory...

First-Principles Calculations on Resistance and Electronic Properties of H2 Adsorption on CoO-SnO2 Heterojunction Surface

2021 ◽  
Author(s):  
Xia Yun He ◽  
Jing Li ◽  
Lin Tao ◽  
Shuai Nie ◽  
Timing Fang ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Synergistic Effect ◽  
Metal Oxides ◽  
Electronic Properties ◽  
First Principles ◽  
Density Functional ◽  
Pure Metal ◽  
First Principles Calculations ◽  
Functional Theory ◽  
H2 Adsorption

Compared with pure metal oxides, heterojunction greatly changes the response to gas by the synergistic effect of interface. In this work, density functional theory was used to reveal the adsorption...

Elastic and electronic properties of oxygen plasma-treated graphene sheets from first principles

2017 ◽  
Vol 31 (08) ◽  
pp. 1750054
Author(s):  
F. Nasehnia ◽  
M. Seifi
Keyword(s):  
Electronic Properties ◽  
Elastic Constants ◽  
Density Functional ◽  
Oxygen Plasma ◽  
Graphene Sheets ◽  
Pristine Graphene ◽  
Functional Theory ◽  
Compressive Loads ◽  
C 50 ◽  
Special Case

Mechanical and electronic properties of oxygen plasma-treated graphene sheets are investigated using density functional theory (DFT). Oxygen plasma-treated graphene is modeled using a graphene sheet with adsorbed epoxide functional groups (C–O–C) on its one side. The most stable configurations of such oxidized graphene sheets with different O/C ratios ranging from 12.5% to 50% are then calculated. In the special case of O/C = 50% (fully oxidized surface), both single- and double-sided oxidation cases are considered. The elastic and electronic properties of the energetically most favorable configurations are evaluated under the tensile and compressive loads in harmonic range. For structures with high O/C ratios (O/C [Formula: see text] 25%), the elastic constants (modulus of elasticity and bulk modulus) are significantly smaller than those of graphene while for low O/C ratios (O/C [Formula: see text] 12.5%), these quantities are almost equal to the elastic constants of pristine graphene. We also found that the electronic bandgap of the oxidized sheets is increased under tensile loading.

scholarly journals A first-principle study on the electronic properties of substitutionally Cu (I, II)-doped LiNbO3

2018 ◽  
Vol 08 (01) ◽  
pp. 1820002 ◽  
Author(s):  
Xiaobin Liu ◽  
Wenxiu Que ◽  
Yucheng He ◽  
Huanfu Zhou
Keyword(s):  
Band Structure ◽  
Band Gap ◽  
Electronic Properties ◽  
First Principles ◽  
Density Functional ◽  
First Principles Calculations ◽  
Density Of State ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Small Band

The electronic properties of Cu-doped lithium niobate (LiNbO3) systems are investigated by first-principles calculations. In this work, we focus on substitutionally Cu[Formula: see text]Li-doped LiNbO3 system with cuprous and cupric doping, which corresponds to the Li[Formula: see text]Cu[Formula: see text]NbO3 and Li[Formula: see text]Cu[Formula: see text]NbO3 [abbreviated as (Li, Cu I)NbO3 and (Li, Cu II)NbO3]. The density functional theory (DFT) calculations show that the electronic property of LiNbO3 is completely different from (Li, Cu I)NbO3 and (Li, Cu II)NbO3. The calculated band structure and density of state (DOS) of (Li, Cu I)NbO3 show a small band gap of 1.34[Formula: see text]eV and the top of valance band (VB) is completely composed of a doping energy level originating from Cu 3d filled orbital. However, the calculated band structure and DOS of (Li, Cu II)NbO3 show a relatively large band gap of 2.22[Formula: see text]eV and the top of VB is mainly composed of Cu 3d unfilled orbital and O 2p orbital.

Sign in / Sign up

Export Citation Format

Share Document