Effect of Carbon Doped in BN on Electronic Structures and Mechanical Properties

2013 ◽  
Vol 652-654 ◽  
pp. 1410-1415
Author(s):  
Jing Ao ◽  
Chun Mei Li ◽  
Zhi Qian Chen ◽  
Jin Wang
Keyword(s):  
Elastic Constants ◽  
Electronic Structures ◽  
Density Functional ◽  
Energy Gap ◽  
Local Density ◽  
Generalized Gradient ◽  
Virtual Crystal Approximation ◽  
Functional Theory ◽  
Carbon Doped ◽  
Ratio Energy

The structural properties and elastic constants of (B1-xCx)(N1-xCx) (x=0.0, 0.2, 0.4 and 0.6) are calculated by the ultra-soft pseudo-potentials within the generalized gradient approximation and local density approximation in frame of density functional theory with virtual crystal approximation. The elastic constants, the aggregate elastic modulus, poisson’s ratio, energy gap and hardness are computed too. The energy band structure, DOS, and Hellmann-Feynman stresses are also examined in details.

Effect of Carbon Doped in BN on Thermodynamic Properties

2013 ◽  
Vol 706-708 ◽  
pp. 85-89
Author(s):  
Jing Ao ◽  
Ai Ling Ding ◽  
Chun Mei Li ◽  
Feng Li ◽  
Jin Wang ◽  
...  
Keyword(s):  
Thermodynamic Properties ◽  
Density Functional ◽  
Local Density ◽  
Debye Model ◽  
Relative Volume ◽  
Density Approximation ◽  
Virtual Crystal Approximation ◽  
Functional Theory ◽  
Carbon Doped ◽  
Temperature And Pressure

The thermodynamic properties of (B1-xCx)(N1-xCx) (x=0, 0.25, 0.5) are calculated by the ultra-soft pseud-potentials within local density approximation in frame of density functional theory with virtual crystal approximation and using the quasi-harmonic Debye model. The normalized relative volume V/V0, bulk modulus, thermal expansion coefficient α and heat capacity were computed with different temperature and pressure. Meanwhile the lower limit of the thermal conductivity κmin is also examined in details.

Density Functional Theory Approach for Muon Sites Estimation in Mn3Sn

2021 ◽  
Vol 1028 ◽  
pp. 199-203
Author(s):  
Fiqhri Heda Murdaka ◽  
Edi Suprayoga ◽  
Abdul Muizz Pradipto ◽  
Kohji Nakamura ◽  
Agustinus Agung Nugroho
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Local Density ◽  
Full Potential ◽  
Theory Approach ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Electrostatic Potential Calculation ◽  
A Site ◽  
Linearized Augmented Plane Wave

We report the estimation of muon sites inside Mn3Sn using density functional theory based on the full-potential linearized augmented plane wave (FLAPW) calculation. Our calculation shows that the Perdew–Burke–Ernzerhof (PBE) Generalized-Gradient Approximation (GGA) functional is closer to the experimental structure compared to the von Barth-Hedin Local Density Approximation (LDA)-optimized geometry. The PBE GGA is therefore subsequently used in FLAPW post-calculation for the electrostatic potential calculation to find the local minima position as a guiding strategy for estimating the muon site. Our result reveals at least two muon sites of which one is placed at the center between two Mn-Sn triangular layers (A site) and the other at the trigonal prismatic site of Sn atom (B site). The total energy of Mn3Sn system in the presence of muon at A site or B site are compared and we find that A site is a more favorable site for muon to stop.

Structural, electronic and elastic properties of the B2-ScM (M =Au, Hg and Tl) intermetallic compounds: Ab initio calculations

2015 ◽  
Vol 04 (04) ◽  
pp. 1550020
Author(s):  
Ahmad A. Mousa ◽  
Jamil M. Khalifeh
Keyword(s):  
Mechanical Properties ◽  
Bulk Modulus ◽  
Intermetallic Compounds ◽  
Elastic Constants ◽  
Density Functional ◽  
Electronic Band Structure ◽  
Local Density ◽  
Full Potential ◽  
Generalized Gradient ◽  
Electronic Band

Structural, electronic, elastic and mechanical properties of ScM (M[Formula: see text][Formula: see text][Formula: see text]Au, Hg and Tl) intermetallic compounds are studied using the full potential-linearized augmented plane wave (FP-LAPW) method based on the density functional theory (DFT), within the generalized gradient approximation (GGA) and the local density approximation (LDA) to the exchange-correlation approximation energy as implemented in the Wien2k code. The ground state properties including lattice parameters, bulk modulus and elastic constants were all computed and compared with the available previous theoretical and experimental results. The lattice constant was found to increase in contrast to the bulk modulus which was found to decrease with every substitution of the cation (M) starting from Au till Tl in ScM. Both the electronic band structure and density-of-states (DOS) calculations show that these compounds possess metallic properties. The calculated elastic constants ([Formula: see text], [Formula: see text] and [Formula: see text] confirmed the elastic stability of the ScM compounds in the B2-phase. The mechanical properties and ductile behaviors of these compounds are also predicted based on the calculated elastic constants.

THEORETICAL INVESTIGATION OF THE ELASTIC PROPERTIES AND LATTICE DYNAMICS OF THE MgSxSe1-x ALLOY

2007 ◽  
Vol 21 (05) ◽  
pp. 249-259 ◽  
Author(s):  
K. BOUAMAMA ◽  
P. DJEMIA
Keyword(s):  
Elastic Properties ◽  
First Principles ◽  
Lattice Dynamics ◽  
Density Functional ◽  
Local Density ◽  
Lattice Parameter ◽  
First Principles Calculations ◽  
Virtual Crystal Approximation ◽  
Functional Theory ◽  
Density Functional Perturbation Theory

Structural and elastic properties as well as lattice dynamics of ternary MgS x Se 1-x alloy have been studied using first-principles calculations. These are done using density functional theory (DFT) and density functional perturbation theory (DFPT) within the local density approximation (LDA) and employing the virtual-crystal approximation (VCA). We found that the lattice parameter, the elastic constants and the phonon frequencies follow a quadratic law in x.

scholarly journals Tuning Electronic Structures of BN and C Double-Wall Hetero-Nanotubes

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Xueran Liu ◽  
Meijun Han ◽  
Xinjiang Zhang ◽  
Haijun Hou ◽  
Shaoping Pang ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Electric Field ◽  
Electronic Structures ◽  
Density Functional ◽  
Transverse Electric ◽  
First Principle ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Double Wall

First principle calculations based on density functional theory with the generalized gradient approximation were carried out to investigate the energetic and electronic properties of carbon and boron nitride double-wall hetero-nanotubes (C/BN-DWHNTs) with different chirality and size, including an armchair (n,n) carbon nanotube (CNT) enclosed in (m,m) boron nitride nanotube (BNNT) and a zigzag (n, 0) CNT enclosed in (m, 0) BNNT. The electronic structure of these DWHNTs under a transverse electric field was also investigated. The ability to tune the band gap with changing the intertube distance (di) and imposing an external electric field (F) of zigzag DWHNTs provides the possibility for future electronic and electrooptic nanodevice applications.

Density Functional Calculations on Electronic and Magnetic Properties of Fe-Pt Systems

2005 ◽  
Vol 475-479 ◽  
pp. 3103-3106 ◽  
Author(s):  
You Song Gu ◽  
Jian He ◽  
Zhen Ji ◽  
Xiao Yan Zhan ◽  
Yue Zhang ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Moment ◽  
Electronic Structures ◽  
Density Functional ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Exchange Correlation ◽  
Generalized Gradient Approximation ◽  
Experimental Values ◽  
Pseudo Potential

The electronic structures and magnetic properties of Fe-Pt systems were calculated by CASTEP codes, which employed density functional theory, generalized gradient approximation (GGA), Perdew Burke Ernzerh exchange correlation, Pulay density-mixing scheme and Ultra Soft pseudo potential. The band structures and density of states (DOS) were calculated, together with band populations and magnetic properties. The calculated results of α-Fe show the validatiy of this method in predication magnetic properties. It is found that as the Pt concentration increases, Fe 4s and 3d electrons decrease while 4p electrons increase, and the magnetic moment of Fe atom increases. Pt atoms also contribute to the magnetic moment due to polarization. The calculated magnetization agrees with experimental values quite well.

scholarly journals Energetics and electronic structures of perylene confined in carbon nanotubes

2018 ◽  
Vol 5 (6) ◽  
pp. 180359 ◽  
Author(s):  
Yuya Nagasawa ◽  
Takeshi Koyama ◽  
Susumu Okada
Keyword(s):  
Carbon Nanotubes ◽  
Density Functional Theory ◽  
Ground State ◽  
Electronic Structures ◽  
Density Functional ◽  
Molecular Conformation ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Molecular Conformations ◽  
Generalized Gradient Approximation

The energetics and geometries of perylene encapsulated in carbon nanotubes (CNTs) have been investigated employing density functional theory using the generalized gradient approximation combined with the van der Waals correction. Our calculations show that the encapsulated perylene molecules possess two metastable molecular conformations with respect to the CNT wall, which are almost degenerate with each other. A standing conformation, with respect to the CNT wall, is the ground state conformation for a semiconducting (19,0)CNT, while a lying conformation is the ground state for a metallic (11,11)CNT. Cooperation and competition between perylene–perylene and perylene–CNT interactions cause these possible perylene conformations inside CNTs. However, the electronic structure of the CNT encapsulating the perylene molecules is found to be insensitive to the molecular conformation.

A comparative study of small 3d-metal oxide (FeO)n, (CoO)n, and (NiO)n clusters

2016 ◽  
Vol 18 (40) ◽  
pp. 27858-27867 ◽  
Author(s):  
G. L. Gutsev ◽  
K. G. Belay ◽  
K. V. Bozhenko ◽  
L. G. Gutsev ◽  
B. R. Ramachandran
Keyword(s):  
Density Functional Theory ◽  
Metal Oxide ◽  
Comparative Study ◽  
Electronic Structures ◽  
Density Functional ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Metal Oxide Clusters ◽  
Generalized Gradient Approximation

Geometrical and electronic structures of the 3d-metal oxide clusters (FeO)n, (CoO)n, and (NiO)n are computed using density functional theory with the generalized gradient approximation in the range of 1 ≤ n ≤ 10.

Ab intio Investigations of Lattice Parameters in ZnMgO Alloys

2009 ◽  
Vol 1201 ◽  
Author(s):  
Markus Heinemann ◽  
Marcel Giar ◽  
Christian Heiliger
Keyword(s):  
Density Functional ◽  
Local Density ◽  
Density Functional Theory Calculations ◽  
Lattice Parameters ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Lattice Constants ◽  
Exchange Correlation ◽  
Vegard’S Law ◽  
Constant Unit

AbstractWe perform density functional theory calculations to determine equilibrium lattice parameters of wurtzite Zn1-xMgxO alloys for Mg concentrations x ranging from 0 to 31.25 %. We use the local density approximation (LDA) as well as the generalized gradient approximation (GGA) for the exchange correlation functional. For the lattice constants a and c we find a deviation from Vegard's law and a constant unit cell volume independent of the Mg concentration.

DFT Study on Geometric and Electronic Structures Properties of Dye Sensitizers

2015 ◽  
Vol 748 ◽  
pp. 197-200
Author(s):  
Mei Juan Cao ◽  
Zhi Cheng Sun ◽  
Lu Hai Li ◽  
Yuan Bin She ◽  
Zuo Lin Yang ◽  
...  
Keyword(s):  
Electronic Transport ◽  
Electronic Structures ◽  
Energy Barrier ◽  
Density Functional ◽  
Energy Gap ◽  
Frontier Molecular Orbital ◽  
Central Metal ◽  
Functional Theory ◽  
Homo And Lumo ◽  
Porphyrin Core

A series of porphyrin sensitizers with different central metal ions (PMn, PFe, PCo, PNi, PCu, and PZn) have been studied based on density functional theory (DFT). The geometric structure of the dyes was optimized and the frontier molecular orbital were calculated. The result shows that the LUMO levels of PFe, PNi and PZn were much lower than that of PMn, PCo and PCu, which suggest a lower energy barrier for electron transfer from the donor to the acceptor tunneling. Furthermore, the energy gap of HOMO and LUMO for PFe was only 0.81 eV, it indicates a significant red shift of the absorption spectrum. The LUMO of PMn, PNi, PCu and PZn were mainly decocalized on the porphyrin core and the bridge moiety, which was beneficial to electronic transport.

Sign in / Sign up

Export Citation Format

Share Document