Structural and Electronic Properties of Pure Ta, TaNO, and TaZrNO with Ab Initio Calculations

ISRN Metallurgy ◽

10.5402/2012/456762 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

T. Chihi ◽

M. Fatmi ◽

M. Guemmaz ◽

J. C. Parlebas

Keyword(s):

Interatomic Distance ◽

Density Functional ◽

Electronic Conductivity ◽

First Principle ◽

Functional Theory ◽

First Principle Calculations ◽

Structural And Electronic Properties ◽

Densities Of States ◽

Self Consistent ◽

The Difference

This paper presents the results of self-consistent first-principle calculations for the crystal structure and electronic structure of pure tantalum, TaNO, and TaZrNO within density functional theory (DFT) for the sake of comparison and shows the influence of allowing elements on the interatomic distance and the Fermi level. The large total densities of states (TDOS) value for TaZrNO implies the highest electronic conductivity. The difference in values is due to the Zr metallic atoms presence in TaZrNO compound. There is a strong interaction between Ta and (N, O) (Ta−N=0.39, Ta−O=0.21) in TaON compound, and Zr presence increases this interaction (Ta−N=1.74, Ta−O=0.30) in TaZrON compound.

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

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.2545 ◽

2013 ◽

Vol 634-638 ◽

pp. 2545-2549 ◽

Cited By ~ 2

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.

AB INITIO CALCULATIONS OF THE CRYSTALLINE AND ELECTRONIC STRUCTURE OF 5-7 FLUOROGRAPHENE VARIETIES

Physical and Chemical Aspects of the Study of Clusters Nanostructures and Nanomaterials ◽

10.26456/pcascnn/2020.12.326 ◽

2020 ◽

pp. 326-337

Author(s):

Максим Евгеньевич Беленков ◽

Владимир Михайлович Чернов

Keyword(s):

Density Functional ◽

Density Functional Theory Method ◽

Band Gaps ◽

First Principle ◽

Functional Theory ◽

Graphene Layers ◽

First Principle Calculations ◽

Deformation Parameters ◽

The Density Functional Theory ◽

Structural And Electronic Properties

Первопринципные расчеты структуры и электронных свойств двух новых полиморфных разновидностей фторографена были выполнены методом теории функционала плотности. Новые слои фторографена могут формироваться при химической адсорбции фтора на поверхности 5 - 7 графеновых слоев. Структура слоя первого типа более деформирована по сравнению со структурой второго типа (деформационные параметры Def = 60,48° и Def = 31,51° ). Энергии сублимации и ширины запрещенных зон составляют 13,85, 14,17 эВ/(CF), и 4,09, 3,32 эВ для CF - L слоев T1, T2 типов соответственно. First-principle calculations of the structural and electronic properties of two new polymorphic varieties of fluorographene were performed using the density functional theory method. New layers of fluorographene can be formed during chemical adsorption of fluorine on the surface of 5 - 7 graphene layers. The structure of the layer of the first type is more deformed in comparison with the structure of the second type (deformation parameters Def = 60,48 ° and Def = 31,51 °). Sublimation energies and band gaps are 13,85, 14,17 eV/(CF), and 4,09, 3,32 eV for CF-L layers of T1, T 2 types, respectively.

First-principle investigations of structural and electronic properties of TMAl (TM = Fe, Co, and Ni) transition metal aluminides

Materials Science-Poland ◽

10.1515/msp-2015-0033 ◽

2015 ◽

Vol 33 (2) ◽

pp. 251-258

Author(s):

Bendouma Doumi ◽

Allel Mokaddem ◽

Mustapha Ishak-Boushaki ◽

Miloud Boutaleb ◽

Abdelkader Tadjer

Keyword(s):

Transition Metal ◽

Electronic Properties ◽

Density Functional ◽

First Principle ◽

Generalized Gradient ◽

Metallic Behavior ◽

Plane Wave Method ◽

Structural And Electronic Properties ◽

The Difference ◽

Metal Aluminides

AbstractIn the present work, we have investigated the structural and electronic properties of TMAl (TM = Fe, Co, and Ni) transition metal aluminides in the B2 structure, using first-principle calculations of the density functional theory (DFT) based on the linearized augmented plane wave method (FP-LAPW) as implemented in the WIEN2k code, in which the energy of exchange and correlation are treated by the generalized gradient approximation (GGA), proposed in 1996 by Perdew, Burke and Ernzerhof (PBE). The ground state properties have been calculated and compared with other calculations, and the electronic structures of all FeAl, CoAl, and NiAl compounds exhibited a metallic behavior. It was depicted that the density of states is characterized by the large hybridization between the s-p (Al) and 3d (Fe, Co, and Ni) states, which creates the pseudogap in the region of anti-bonding states. Moreover, the band structures of FeAl, CoAl, and NiAl are similar to each other and the difference between them is in the energy level of each band relative to the Fermi level.

First Principles Study on Structural and Electronic Properties of LiFeSO4OH Cathode Material for Lithium Ion Batteries

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.510.33 ◽

2014 ◽

Vol 510 ◽

pp. 33-38 ◽

Cited By ~ 1

Author(s):

F.W. Badrudin ◽

M.S.A. Rasiman ◽

M.F.M. Taib ◽

N.H. Hussin ◽

O.H. Hassan ◽

...

Keyword(s):

Density Functional Theory ◽

Cathode Material ◽

Electronic Properties ◽

First Principles ◽

Density Functional ◽

Electronic Conductivity ◽

Lithium Ion ◽

Density Of State ◽

Functional Theory ◽

Structural And Electronic Properties

Structural and electronic properties of a new fluorine-free cathode material of polyanionichydroxysulfates, LiFeSO4OH withcaminitestructure are studied using first principles density functional theory. From the calculated result, it reveals that antiferromagnetic configuration is more stable compared to ferromagnetic and non-magnetic configuration. Meanwhile, the density of state calculation divulges that this material exhibited large d-d type of band gap and would behave as a Mott-Hubbard insulator. Thus, this behaviour can lead to poor electronic conductivity.

Anisotropically Nanostructured Silicon: A First-Principle Approach.

MRS Proceedings ◽

10.1557/proc-832-f10.8 ◽

2004 ◽

Vol 832 ◽

Author(s):

Yuri Bonder ◽

Chumin Wang

Keyword(s):

Experimental Data ◽

Density Functional ◽

First Principle ◽

Hydrogen Atoms ◽

Functional Theory ◽

Nanostructured Silicon ◽

Plane Anisotropy ◽

The Density Functional Theory ◽

The Difference ◽

Good Agreement

ABSTRACTOptical properties of birefringent porous-silicon layers are studied within the density functional theory. Starting from a (110)-oriented supercell of 32 silicon atoms, columns of atoms in directions [100] and [010] are removed and the dangling bonds are saturated with hydrogen atoms. The results show an in-plane anisotropy in the dielectric function and in the refractive index (n). The difference Δn defined as n[110] -n[001] is compared with experimental data and a good agreement is observed. Also, the possibility in determining the morphology of pores by using polarized lights is analyzed.

Electronic Structures of Vacancy Defective Chiral (6,2) SiC Nanotubes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.896.3 ◽

2017 ◽

Vol 896 ◽

pp. 3-8

Author(s):

Ke Jian Li ◽

Hong Xia Liu

Keyword(s):

Density Functional Theory ◽

Silicon Carbide ◽

Electronic Structures ◽

Density Functional ◽

First Principle ◽

Defect Level ◽

Functional Theory ◽

Vacancy Defects ◽

First Principle Calculations ◽

Silicon Carbide Nanotubes

Vacancy defects are common defects formed in the syntheses of silicon carbide nanotubes (SiCNTs) and seriously impact the electronic structures of the nanotubes. With first-principle calculations based on density functional theory (DFT), vacancy defective (6,2) SiCNTs are studied. Vacancies form a pair of fivefold and ninefold rings. Carbon vacancy introduces an occupied defect level near the top of the valence band and an unoccupied level in the conduction band. Three defect levels are found in the band gap of the SiCNT with a silicon vacancy. These results are helpful for investigations on SiCNT devices and sensors.

Theoretical Analysis of the DOS and Band Structural Properties of Ti1-XSnxO2 Solid Solutions

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.465.33 ◽

2012 ◽

Vol 465 ◽

pp. 33-36

Author(s):

Zhi Dong Lin ◽

Wen Long Song ◽

Ju Cheng Zheng

Keyword(s):

Band Gap ◽

Solid Solutions ◽

Density Functional ◽

Wide Band ◽

Low Energy ◽

Low Density ◽

First Principle ◽

Wide Band Gap ◽

Functional Theory ◽

First Principle Calculations

The band structure and density of states (DOS) of Ti1-xSnxO2 solid solutions with x=0, 1/8, 1/4, 1/2 and 1 were investigated by means of the first-principle calculations based on density functional theory. The result indicated that band gap and Fermi level of TiO2-SnO2 vary continuously from those of pure TiO2 to those of Sn content increasing. In addition, the DOS moves towards low energy and the bang gap is broadened with growing value of x. The wide band gap and the low density of the states in the conduction band result in the enhancement of photoactivity in Ti1-xSnxO2.

Elastic and optical properties of sillenites: First principle calculations

Ferroelectrics ◽

10.1080/00150193.2020.1713354 ◽

2020 ◽

Vol 557 (1) ◽

pp. 98-104 ◽

Cited By ~ 1

Author(s):

Husnu Koc ◽

Selami Palaz ◽

Sevket Simsek ◽

Amirullah M. Mamedov ◽

Ekmel Ozbay

Keyword(s):

Optical Properties ◽

Electronic Structures ◽

Density Functional ◽

Electronic Band Structure ◽

First Principle ◽

Electronic Band ◽

Functional Theory ◽

First Principle Calculations ◽

Optical Functions ◽

The Density Functional Theory

In the present paper, we have investigated the electronic structure of some sillenites - Bi12MO20 (M = Ti, Ge, and Si) compounds based on the density functional theory. The mechanical and optical properties of Bi12MO20 have also been computed. The second-order elastic constants have been calculated, and the other related quantities have also been estimated in the present work. The band gap trend in Bi12MO20 can be understood from the nature of their electronic structures. The obtained electronic band structure for all Bi12MO20 compounds is semiconductor in nature. Similar to other oxides, there is a pronounced hybridization of electronic states between M-site cations and anions in Bi12MO20. Based on the obtained electronic structures, we further calculate the frequency-dependent dielectric function and other optical functions.

First Principle Calculations for Silver Halides AgBr, AgCl, and AgF

ARO-The Scientific Journal of Koya University ◽

10.14500/aro.10874 ◽

2021 ◽

Vol 9 (2) ◽

pp. 71-75

Author(s):

Akram H. Taha

Keyword(s):

Electronic Structures ◽

Density Functional ◽

Total Density ◽

First Principle ◽

Silver Halides ◽

Functional Theory ◽

First Principle Calculations ◽

Almost All ◽

Total Density Of States ◽

Good Agreement

Density functional theory (DFT) coupled with ) method are carried out to calculate the electronic structures of AgX (X; Br, Cl, and F). The effect of hybridizing between 4d orbital of Ag element and the p orbitals of the X in the valence band plays a very important role in the total density of states configuration. The electronic structure has been studied and all results were compared with the experimental and theoretical values. The importance of this work is that there is insufficient studies of silver halides corresponding the great importance of these compounds. Almost all the results were consistent with the previous studies mentioned here. We found the band gap of AgX to be 2.343 eV, 2.553 eV, and 1.677 eV for AgBr, AgCl, and AgF respectively which are in good agreement with the experimental results.

First-Principle Investigation of Lithium Intercalation Behavior of a (3, 3) Carbon Nanotube

Materials Science Forum ◽

10.4028/www.scientific.net/msf.736.27 ◽

2012 ◽

Vol 736 ◽

pp. 27-31

Author(s):

Kulpreet Singh Virdi ◽

K.C. Hari Kumar

Keyword(s):

Density Functional Theory ◽

Carbon Nanotube ◽

Density Functional ◽

Lithium Atom ◽

Energy Difference ◽

Lithium Intercalation ◽

First Principle ◽

Tube Axis ◽

Functional Theory ◽

First Principle Calculations

Using first-principle calculations employing density functional theory (DFT) the stabilityof a (3, 3) carbon nanotube (CNT) intercalated with lithium atoms, with respect to their position aswell as Li/C ratio, is studied. On varying the distance of a lithium atom from the axis of the CNT in theradial direction, through the center of a graphitic hexagon, minimum of energy of the system occursat a distance of 3.8 °A from the axis. Keeping the distance of the lithium atom from the tube axis fixedat 3.8 °A, intercalation energy (E) was calculated while the number of lithium atoms is varied fromone (Li1C12, −0.511 eV) to six (Li6C12, −0.615 eV). It is found that the intercalation becomes morefavorable with the increase in number of lithium atoms intercalated and increase in the symmetryof the intercalated system. The maximum intercalation energy difference between successive lithiumatom additions lay within 0.1 eV.