scholarly journals Topological Dirac Semimetal Phase in Bismuth Based Anode Materials for Sodium-Ion Batteries

2020 ◽  
Vol 5 (2) ◽  
pp. 39
Author(s):  
Wei-Chi Chiu ◽  
Bahadur Singh ◽  
Sougata Mardanya ◽  
Johannes Nokelainen ◽  
Amit Agarwal ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Density Functional ◽  
Generalized Gradient ◽  
Band Shift ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Dirac Semimetal ◽  
Structural And Electronic Properties ◽  
Structure Density

Bismuth has recently attracted interest in connection with Na-ion battery anodes due to its high volumetric capacity. It reacts with Na to form Na 3 Bi which is a prototypical Dirac semimetal with a nontrivial electronic structure. Density-functional-theory based first-principles calculations are playing a key role in understanding the fascinating electronic structure of Na 3 Bi and other topological materials. In particular, the strongly-constrained-and-appropriately-normed (SCAN) meta-generalized-gradient-approximation (meta-GGA) has shown significant improvement over the widely used generalized-gradient-approximation (GGA) scheme in capturing energetic, structural, and electronic properties of many classes of materials. Here, we discuss the electronic structure of Na 3 Bi within the SCAN framework and show that the resulting Fermi velocities and s-band shift around the Γ point are in better agreement with experiments than the corresponding GGA predictions. SCAN yields a purely spin-orbit-coupling (SOC) driven Dirac semimetal state in Na 3 Bi in contrast with the earlier GGA results. Our analysis reveals the presence of a topological phase transition from the Dirac semimetal to a trivial band insulator phase in Na 3 Bi x Sb 1 − x alloys as the strength of the SOC varies with Sb content, and gives insight into the role of the SOC in modulating conduction properties of Na 3 Bi.

scholarly journals Electronic Structure and Optical Properties ofGaAs1-xBixAlloy

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Xindong You ◽  
Renjie Zhou
Keyword(s):  
First Principles ◽  
Density Functional ◽  
Optical Constants ◽  
Optical Transition ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Zinc Blende ◽  
Structural And Electronic Properties ◽  
Zinc Blende Structure

A first-principles study has been performed to investigate the structural and electronic properties of theGaAs1-xBixsystem. The simulations are based upon the generalized gradient approximation (GGA) within the framework of density functional theory (DFT). Calculations are performed to different Bi concentrations. The lattice constant ofGaAs1-xBixincreases with Bi concentration while the alloy remains in the zinc-blende structure. The band gap ofGaAs1-xBixclearly shrinks with the Bi concentration. The optical transition of Bi dopant in GaAs exhibits a red shift. Besides, other important optical constants, such as the dielectric function, reflectivity, refractive index, and loss function also change significantly.

FIRST-PRINCIPLES STUDY OF STRUCTURAL AND ELECTRONIC PROPERTIES OF SrLiSb UNDER HIGH PRESSURE

2012 ◽  
Vol 26 (29) ◽  
pp. 1250151
Author(s):  
Z. H. YU ◽  
C. Y. LI ◽  
H. Z. LIU
Keyword(s):  
High Pressure ◽  
Electronic Properties ◽  
First Principles ◽  
Density Functional ◽  
Geometry Optimization ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Electronic Phase ◽  
Structural And Electronic Properties

Using the first-principles plane wave pseudopotential method, the structural and electronic properties of intermetallic compound SrLiSb have been studied within generalized gradient approximation in the frame of density functional theory. The calculations of lattice parameters are in well agreement with the available experimental data. The geometry optimization results indicated the compressibility of SrLiSb is anisotropic under high pressure. The energy band structure and density of states of SrLiSb were also calculated, indicating that SrLiSb has an electronic phase transition from direct-gap semiconductor to indirect-gap semiconductor at approximate 8 GPa.

First-Principle Study of Structural and Electronic Properties of Ti-Doped SnO2

2013 ◽  
Vol 634-638 ◽  
pp. 2545-2549 ◽  
Author(s):  
Jing Kai Yang ◽  
Hong Li Zhao ◽  
Yan Zhu ◽  
Li Ping Zhao ◽  
Jian Li
Keyword(s):  
Electronic Properties ◽  
Density Functional ◽  
First Principle ◽  
Generalized Gradient ◽  
Functional Theory ◽  
First Principle Calculations ◽  
Generalized Gradient Approximation ◽  
The Density Functional Theory ◽  
Structural And Electronic Properties ◽  
Calculation Results

The structural and electronic properties of Ti-doped SnO2with 6.25 at.% are investigated with the first principle calculations based on the density functional theory within the generalized gradient approximation. The calculation results indicate that the crystal structure of Sn0.9375Ti0.0625O2possesses a smaller volume; the bond length of Ti-O is shorter than that of Sn-O; the relative angle θ change value of Sn-O-Sn→Ti-O-Ti is about 1.07%. Ti-O bond possesses more covalent ingredient and stronger bond energy than Sn-O bond. After the replacement of one Ti atom, O atom bonded with Ti atom possessed fewer electrons, the ratio of charges possessed by Ti atom and O atom dose not agree with the stoichiometry of compound, create more holes at the top of VB of Sn0.9375Ti0.0625O2, and lead to the increase of the conductivity.

A DFT study of structural and electronic properties of Zn1−xSbxTe with x = (0.25,0.50,0.75)

2017 ◽  
Vol 31 (01) ◽  
pp. 1650249
Author(s):  
Diwaker ◽  
Ashwani Kumar
Keyword(s):  
Electronic Properties ◽  
Density Functional ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Text Type ◽  
Exchange Correlation ◽  
Generalized Gradient Approximation ◽  
The Density Functional Theory ◽  
Structural And Electronic Properties ◽  
Sb Doping

In the present work, we report the structural and the electronic properties of the alloy [Formula: see text] with [Formula: see text] and [Formula: see text]. Ab initio calculations are based upon the density functional theory with generalized gradient approximation and Perdew–Burke–Ernzerhof (PBE) exchange–correlation functional. In our calculations, we found that antimony (Sb) doping in zinc telluride (ZnTe) system introduces some bands which mainly originate from [Formula: see text]- and [Formula: see text]-states of Te and Sb atom and are primarily responsible for [Formula: see text]-type and [Formula: see text]-type conductivity.

Electronic structure and density of states in hexagonal BaMnO3

2018 ◽  
Vol 32 (17) ◽  
pp. 1850186 ◽  
Author(s):  
R. F. Hashimov ◽  
N. A. Ismayilova ◽  
F. A. Mikailzade ◽  
A. O. Dashdemirov ◽  
A. V. Trukhanov ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Density Of States ◽  
Density Functional ◽  
Local Density ◽  
Metallic Structure ◽  
Ambient Conditions ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Exchange Correlation ◽  
Generalized Gradient Approximation

The electronic structure and density of states (DOS) of BaMnO3 compound are studied in the framework of density functional theory (DFT) using the generalized gradient approximation (GGA) and local density approximation (LDA). A number of different exchange-correlation functionals including hybrid (PBE, PZ and BLYP) exchange techniques have been used. The results show that in ambient conditions, the compound has metallic structure. It has been found from DOS calculations that the overlapping of bands near the Fermi energy are mainly due to the 3d state of Mn atoms.

A density functional study on the electronic structure, nature of bonding and reactivity of NO adsorbing Rh0/±n (n = 2–8) clusters

2018 ◽  
Vol 42 (2) ◽  
pp. 1121-1132 ◽  
Author(s):  
Abhijit Dutta ◽  
Paritosh Mondal
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Gas Phase ◽  
Density Functional ◽  
Functional Study ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Density Functional Study ◽  
Generalized Gradient Approximation

Systematic investigations on lowest energy NO adsorbing neutral and ionic Rhn (n = 2–8) clusters in the gas phase are executed with an all electron relativistic method using density functional theory (DFT) within the generalized gradient approximation.

scholarly journals Density Functional Theory Evaluated for Structural and Electronic Properties of 1T-LixTiS2 and Lithium Ion Migration in 1T-Li0.94TiS2

2017 ◽  
Vol 231 (7-8) ◽  
Author(s):  
Vanessa Werth ◽  
Kai Volgmann ◽  
Mazharul M. Islam ◽  
Paul Heitjans ◽  
Thomas Bredow
Keyword(s):  
Density Functional Theory ◽  
Electronic Properties ◽  
Density Functional ◽  
Lithium Ion ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Ion Migration ◽  
Generalized Gradient Approximation ◽  
Structural And Electronic Properties ◽  
Weak Chemical

AbstractIn many applications it has been found that the standard generalized gradient approximation (GGA) does not accurately describe weak chemical bond and electronic properties of solids containing transition metals. In this work, we have considered the intercalation material 1T-Li

Dissociation of dinitrogen on iron clusters: A detailed study of the Fe16 + N2 case.

2020 ◽  
Author(s):  
Bole Chen ◽  
Gennady L. Gutsev ◽  
Weiguo Sun ◽  
Xiao-Yu Kuang ◽  
Cheng Lu ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Basis Set ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Iron Clusters ◽  
Generalized Gradient Approximation

The coalescence of two Fe8N as well as the structure of the Fe16N2 cluster were studied using density functional theory with the generalized gradient approximation and a basis set of...

Sign in / Sign up

Export Citation Format

Share Document