scholarly journals Charge Distribution in YBa2Cu3O7 and YBa2Cu4O8 by Density Functional Theory

2016 ◽  
Vol 846 ◽  
pp. 561-566 ◽  
Author(s):  
Choon Min Cheong ◽  
Md Mahmudur Rahman ◽  
Abdul Halim Shaari ◽  
Soo Kien Chen
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Charge Distribution ◽  
Density Of States ◽  
Density Functional ◽  
Lattice Parameters ◽  
Band Structures ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Experimental Parameters

In this work, we analyze the electronic structure and charge distribution of the YBCO family compounds Y-123 and Y-124 bulk using the density functional theory. The band structures and the density of states of the compounds are shown. The charge transfers between the atoms in the two compounds are compared and discussed in detail. The lattice parameters obtained by Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm are compared with the experimental parameters. The critical differences of the charge distribution for these two compounds are discussed.

Study on the Effect of Doping on Lattice Constant and Electronic Structure of Bulk AuCu by the Density Functional Theory

2019 ◽  
Vol 11 (02) ◽  
pp. 2030001 ◽  
Author(s):  
Dung Nguyen-Trong ◽  
Cuong Nguyen-Chinh ◽  
Van Duong-Quoc
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Electronic Properties ◽  
Lattice Constant ◽  
Density Of States ◽  
Impurity Concentration ◽  
Density Functional ◽  
Unit Cell ◽  
Functional Theory ◽  
The Density Functional Theory

This paper studies the effect of GGA-PBE, GGA-PBEsol, GGA-PW91, GGA-VWN-BP, LDA-PWC, LDA-VWN parameterized exchange–correlation functionals and Cu impurity concentration on the lattice and electronic properties of bulk AuCu by the Density Functional Theory (DFT). The lattice properties are determined by the lattice constant, the unit cell volume and the total energy on unit cell. The electronic properties are determined by the band gap, the Partial Density of States (PDOS) and the total Density of States (DOS) of materials. The obtained results showed the effect of the interaction potential and the Cu impurity concentration on the lattice structure and the electronic structure of bulk AuCu.

Effects of vanadium impurity on TiO2 properties

2015 ◽  
Vol 29 (15) ◽  
pp. 1550094 ◽  
Author(s):  
Arvids Stashans ◽  
Jairo Escobar
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Density Of States ◽  
Density Functional ◽  
Magnetic Moments ◽  
Equilibrium Geometry ◽  
Dft Studies ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Atomic Rearrangement

Our present work is based on the density functional theory (DFT) studies of TiO 2 crystals doped with V impurities. Both rutile and anatase structures have been considered within the present research and different defect concentrations have been used as well. Our calculations reveal equilibrium geometry of the system showing atomic rearrangement around the point defect being mainly inward with respect to the impurity. Magnetism and electronic structure based on the density of states (DOS) patterns for both rutile and anatase crystals have been obtained and discussed in detail. It is shown that local magnetic moments arise mainly from the 3d states of the impurity atom with some admixture of 2p states from the vanadium-nearest O atoms.

scholarly journals A look at the density functional theory zoo with the advanced GMTKN55 database for general main group thermochemistry, kinetics and noncovalent interactions

2017 ◽  
Vol 19 (48) ◽  
pp. 32184-32215 ◽  
Author(s):  
Lars Goerigk ◽  
Andreas Hansen ◽  
Christoph Bauer ◽  
Stephan Ehrlich ◽  
Asim Najibi ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Density Functional ◽  
Noncovalent Interactions ◽  
Main Group ◽  
Density Functionals ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Benchmark Database ◽  
Electronic Structure Methods

We present the updated and extended GMTKN55 benchmark database for more accurate and extensive energetic evaluation of density functionals and other electronic structure methods with detailed guidelines for method users.

scholarly journals Theoretical design of a technetium-like alloy and its catalytic properties

2019 ◽  
Vol 10 (21) ◽  
pp. 5461-5469
Author(s):  
Wei Xie ◽  
Michihisa Koyama
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Catalytic Activity ◽  
Density Of States ◽  
Phase Stability ◽  
Density Functional ◽  
Catalytic Properties ◽  
Functional Theory ◽  
Theoretical Design ◽  
Structure Phase

Based on the concept of density of states (DOS) engineering, we theoretically designed a pseudo-Tc material (Mo–Ru alloy) and investigated its electronic structure, phase stability and catalytic activity by using density functional theory.

A STUDY ON STRAIN AFFECTING ELECTRONIC STRUCTURE OF WURTZITE ZnO BY FIRST PRINCIPLES

2009 ◽  
Vol 23 (19) ◽  
pp. 2339-2352 ◽  
Author(s):  
LI BIN SHI ◽  
SHUANG CHENG ◽  
RONG BING LI ◽  
LI KANG ◽  
JIAN WEI JIN ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Band Structure ◽  
Valence Band ◽  
Density Of States ◽  
First Principles ◽  
Density Functional ◽  
Functional Theory ◽  
Electron Density Difference ◽  
Different Strains

Density of states and band structure of wurtzite ZnO are calculated by the CASTEP program based on density functional theory and plane-wave pseudopotential method. The calculations are carried out in axial and unaxial strains, respectively. The results of density of states in different strains show that the bottom of the conduction band is always dominated by Zn 4s, and the top of valence band is always dominated by O 2p. The variation of the band gap calculated from band structure is also discussed. In addition, p-d repulsion is used in investigating the variation of the top of the valence band in different strains and the results can be verified by electron density difference.

scholarly journals Electronic structure of complexes of oligomers of 3,4-ethylene-dietoxythiophene with polystyrlesulphonic acid

Surface ◽  
2021 ◽  
Vol 13(28) ◽  
pp. 84-93
Author(s):  
M. I. Terebinska ◽  
O. I. Tkachuk ◽  
A. M. Datsyuk ◽  
O. V. Filonenko ◽  
V. V. Lobanov
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Charge Distribution ◽  
Electronic Structures ◽  
Density Functional ◽  
Spiral Structure ◽  
Energy Gap ◽  
Conductive Polymer ◽  
Functional Theory ◽  
Method Of Density Functional

By the method of density functional theory (B3LYP, 6-31G **) the electronic structures of poly 3,4-ethylenedioxythiophene containing 12 links in charge states 0, +1, +2, +3 and +4 were calculated. It is shown that the oligomer of 12 units is sufficient to reflect the properties of the conductive polymer. To estimate the probability of electron density movement along the polymer chain, the width of the energy gap between NOMO and LUMO was calculated. It is shown that the molecules of oligomers EDOT and SS do not remain parallel to each other after polymerization, but rather, with increasing chain length, the latter gradually bends around the anionic unit SS; the charge distribution in the EDOT and SS oligomer complexes indicates the presence of two separated polarons at the two ends of the chain, and the asymmetry in the charge distribution also implies the presence of a curved spiral structure of the formed complex.

scholarly journals CALCULATION OF THE ELECTRONIC STRUCTURE OF SOME EPOXY MOLECULES BY THE DFT METHOD

2021 ◽  
pp. 32-34
Author(s):  
V. A. Babkin ◽  
D. S. Andreev ◽  
E. S. Titova ◽  
A. V. Ignatov ◽  
R. O. Boldyrev ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Quantum Chemical Calculation ◽  
Quantum Chemical ◽  
Density Functional ◽  
Dft Method ◽  
Chemical Calculation ◽  
Functional Theory ◽  
The Density Functional Theory

In this work, we performed a quantum-chemical calculation of some epoxy molecules: 1,2-epoxy-butene, 1,2-epoxy-2-methylpropane, 1,2 epoxyethane by the density functional theory DFT. An optimized geometric and electronic structure of these compounds is obtained. It was found that the studied epoxides belong to the class of very weak СH-acids (pKa = 28-30).

Sign in / Sign up

Export Citation Format

Share Document