Calculation Of Positron Characteristics In Silicon Carbide

ABSTRACTPositron affinity calculations performed by a first-principles approach based on density functional theory reveal, contrary to many other semiconductors, that free positrons and positronium atoms can escape from SiC. It is found that the treatment of the electronpositron interaction plays a crucial role when calculating the annihilation characteristics. These characteristics originating from both valence and core electrons, combined with the corresponding measurements, yield a very useful tool for surface studies and point defect identification in the bulk. Calculations will be compared with available experimental data.

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First Principles Studies on Structural, Electronic and Optical Properties of SnO2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.900.203 ◽

2014 ◽

Vol 900 ◽

pp. 203-208 ◽

Cited By ~ 1

Author(s):

Ting Ting Shao ◽

Fu Chun Zhang ◽

Wei Hu Zhang

Keyword(s):

Experimental Data ◽

Density Functional Theory ◽

Optical Properties ◽

Plane Wave ◽

Qualitative Analysis ◽

First Principles ◽

Density Functional ◽

Density Of State ◽

Functional Theory ◽

Electronic And Optical Properties

The structural, electronic, and optical properties of rutile-type SnO2 are studied by plane-wave pseudopotential density functional theory (DFT) with GGA, LDA, B3LYP and PBE0 respectively. The computing results show that the band gap getting from PBE0 and B3LYP is much more consistent with the available experimental data than that from GGA and LDA, no matter what the latter use ultra-soft pseudopotential or norm conserving pseudopotential. However, the density of state, real part and imaginary part of dielectric function calculating from every type is basically similar in qualitative analysis.

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Density functional theory study on the electron spectra of naphthalene and azulene vapours

Canadian Journal of Chemistry ◽

10.1139/v10-041 ◽

2010 ◽

Vol 88 (8) ◽

pp. 787-796 ◽

Cited By ~ 9

Author(s):

Delano P. Chong

Keyword(s):

Experimental Data ◽

Density Functional Theory ◽

Gas Phase ◽

Density Functional ◽

Density Functional Theory Study ◽

Excitation Energies ◽

Excitation Spectra ◽

Functional Theory ◽

Electron Spectra ◽

Core Electrons

The ionization and excitation spectra of valence and core electrons of naphthalene and azulene in the gas phase are studied with density functional theory. The results are compared with available experimental data and previous calculations. New estimates are proposed for the ionization energies of both valence and core electrons and the calculated excitation energies are consistent with experiment.

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Catalyic conversion of hydrocarbons in zeolites from first principles

Pure and Applied Chemistry ◽

10.1351/pac200274112097 ◽

2002 ◽

Vol 74 (11) ◽

pp. 2097-2100 ◽

Cited By ~ 5

Author(s):

Ľubomír Benco ◽

Thomas Demuth ◽

François Hutschka

Keyword(s):

Experimental Data ◽

Molecular Dynamics ◽

Density Functional Theory ◽

First Principles ◽

Spectral Properties ◽

Density Functional ◽

Industrial Process ◽

Reaction Pathways ◽

Functional Theory ◽

Data Comparison

The application of the density functional techniques to processes of the conversion of hydrocarbons in zeolites has been reviewed. The conversion of hydrocarbons over zeolites is an important industrial process. The microscopic steps of the conversion, however, are still not satisfactorily understood. In order to examine reaction pathways, both static and molecular dynamics density functional theory (DFT) calculations have been performed. Simulated structural and spectral properties compare reasonably with experimental data. Comparison of energies of physisorption and chemisorption indicates possible reaction channel of the conversion through the chemisorption at the specific O-sites of the zeolite.

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Properties of Novel Thermoelectrics from First Principles Calculations

MRS Proceedings ◽

10.1557/proc-545-3 ◽

1998 ◽

Vol 545 ◽

Cited By ~ 6

Author(s):

D. J. Singh ◽

I. I. Mazin ◽

J. L. Feldman ◽

M. Fornari

Keyword(s):

Experimental Data ◽

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

Low Frequency ◽

Scattering Data ◽

First Principles Calculations ◽

Phonon Modes ◽

Functional Theory ◽

Filled Skutterudites

AbstractThe use of first principles methods based on density functional theory to investigate novel thermoelectric materials is illustrated for several empty and filled skutterudite compounds, including CoSb3, COP3, La(Fe,Co)4Sb12 and La(Fe,Co)P12. Band structures and their relationship to transport properties especially as regards optimization of thermoelectric properties is discussed. Phonon models constructed from calculations and existing experimental data for CoSb3 are presented. These have been extended to the filled skutterudites, particularly LaFe4Sb12 using additional first principles calculations to fix the La related parameters in the model. This model allows an interpretation of neutron scattering data as well as an understanding of the low frequency phonon modes that transport heat in these compounds.

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Electronic transport properties of silicon carbide molecular junctions: first-principles study

RSC Advances ◽

10.1039/c6ra11028b ◽

2016 ◽

Vol 6 (94) ◽

pp. 91453-91462 ◽

Cited By ~ 4

Author(s):

Yi Mu ◽

Zhao-Yi Zeng ◽

Yan Cheng ◽

Xiang-Rong Chen

Keyword(s):

Density Functional Theory ◽

Silicon Carbide ◽

Transport Properties ◽

Electronic Transport ◽

First Principles ◽

Density Functional ◽

Function Method ◽

Functional Theory ◽

Electronic Transport Properties ◽

Non Equilibrium Green’S Function

The contact geometry and electronic transport properties of a silicon carbide (SiC) molecule coupled with Au (1 0 0) electrodes are investigated by performing density functional theory plus the non-equilibrium Green's function method.

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The Damping Term, from First Principles

10.1093/oso/9780198788669.003.0006 ◽

2017 ◽

Author(s):

Olle Eriksson ◽

Anders Bergman ◽

Lars Bergqvist ◽

Johan Hellsvik

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

Spin Dynamics ◽

Damping Term ◽

Functional Theory ◽

Basic Principles ◽

Sham Equation ◽

Damping Parameter ◽

Simulation Cell

In the previous chapters we described the basic principles of density functional theory, gave examples of how accurate it is to describe static magnetic properties in general, and derived from this basis the master equation for atomistic spin-dynamics; the SLL (or SLLG) equation. However, one term was not described in these chapters, namely the damping parameter. This parameter is a crucial one in the SLL (or SLLG) equation, since it allows for energy and angular momentum to dissipate from the simulation cell. The damping parameter can be evaluated from density functional theory, and the Kohn-Sham equation, and it is possible to determine its value experimentally. This chapter covers in detail the theoretical aspects of how to calculate theoretically the damping parameter. Chapter 8 is focused, among other things, on the experimental detection of the damping, using ferromagnetic resonance.

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Electron-phonon interaction in In-induced √7 ×√3 structures on Si(111) from first-principles

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05234e ◽

2021 ◽

Author(s):

I. Yu. Sklyadneva ◽

Rolf Heid ◽

Pedro Miguel Echenique ◽

Evgueni Chulkov

Keyword(s):

Density Functional Theory ◽

Double Layer ◽

First Principles ◽

Linear Response ◽

Density Functional ◽

Single Layer ◽

Phonon Interaction ◽

Functional Theory ◽

Electron Phonon Interaction ◽

The Density Functional Theory

Electron-phonon interaction in the Si(111)-supported rectangular √(7 ) ×√3 phases of In is investigated within the density-functional theory and linear-response. For both single-layer and double-layer √(7 ) ×√3 structures, it...

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Adsorption of the Gas Molecules (NH3, C2H6O, C3H6O, CO, H2S) on noble metal (Ag, Au, Pt, Pd, Ru)–Doped MoSe2 Monolayer: A First-Principles Study

New Journal of Chemistry ◽

10.1039/d1nj01705e ◽

2021 ◽

Author(s):

Lanjuan Zhou ◽

Sujing Yu ◽

Yan Yang ◽

Qi Li ◽

Tingting Li ◽

...

Keyword(s):

Density Functional Theory ◽

Noble Metal ◽

First Principles ◽

Density Functional ◽

Noble Metals ◽

Gas Sensing ◽

Functional Theory ◽

First Principles Study ◽

Gas Molecules ◽

Sensing Performance

In this paper, the effects of five noble metals (Au, Pt, Pd, Ag, Ru) doped MoSe2 on improving gas sensing performance were predicted through density functional theory (DFT) based on...

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Geometric, electronic properties of Au$_l$Pt$_m$ ($l$+$m$$\leqslant$10) clusters: A first-principles study

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05642a ◽

2021 ◽

Author(s):

Wei-Feng Xie ◽

Hao-Ran Zhu ◽

Shi-Hao Wei

Keyword(s):

Density Functional Theory ◽

Electronic Properties ◽

First Principles ◽

Density Functional ◽

Inverse Design ◽

Functional Theory ◽

First Principles Study

The structural evolutions and electronic properties of Au$_l$Pt$_m$ ($l$+$m$$\leqslant$10) clusters are investigated by using the first$-$principles methods based on density functional theory (DFT). We use Inverse design of materials by...

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The stability and electronic and photocatalytic properties of the ZnWO4 (010) surface determined from first-principles and thermodynamic calculations

RSC Advances ◽

10.1039/d1ra03218f ◽

2021 ◽

Vol 11 (38) ◽

pp. 23477-23490

Author(s):

Yonggang Wu ◽

Jihua Zhang ◽

Bingwei Long ◽

Hong Zhang

Keyword(s):

Phase Diagram ◽

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

Thermodynamic Calculations ◽

Photocatalytic Properties ◽

Thermodynamic Approach ◽

Functional Theory ◽

Stability Phase Diagram ◽

The Stability

The ZnWO4 (010) surface termination stability is studied using a density functional theory-based thermodynamic approach. The stability phase diagram shows that O-Zn, DL-W, and DL-Zn terminations of ZnWO4 (010) can be stabilized.

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