First-Principles Simulations of Frenkel Pair Formation and Annealing in Irradiated ß-SiC

Using first principles molecular dynamics and Nudged Elastic Band calculations, we have investigated the effect of irradiation on cubic silicon carbide at the atomic scale, and in particular the formation of Frenkel pairs, and the crystal recovery after thermal treatment. Threshold displacement energies have been determined for C and Si sublattice, and the stability and structure of the formed Frenkel pairs are described. The activation energies for annealing these defects have then been computed and compared with experiments.

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Ab Initio Investigations of Threshold Displacement Energies and Stability of Associated Defects in Cubic Silicon Carbide

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.108-109.671 ◽

2005 ◽

Vol 108-109 ◽

pp. 671-676

Author(s):

Guillaume Lucas ◽

Laurent Pizzagalli

Keyword(s):

Molecular Dynamics ◽

Silicon Carbide ◽

First Principles ◽

Transition State Theory ◽

State Theory ◽

The Stability ◽

Dynamics Simulations ◽

Cubic Silicon Carbide ◽

Threshold Displacement ◽

Good Agreement

Using first principles molecular dynamics simulations, we have recently determined the threshold displacement energies and the associated created defects in cubic silicon carbide. Contrary to previous studies using classical molecular dynamics, we found values close to the experimental consensus, and also created defects in good agreement with recent works on interstitials stability in silicon carbide. We have also investigated the stability of several Frenkel pairs, using transition state theory and constrained path calculations.

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Graphite, graphene on SiC, and graphene nanoribbons: Calculated images with a numerical FM-AFM

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.3.34 ◽

2012 ◽

Vol 3 ◽

pp. 301-311 ◽

Cited By ~ 12

Author(s):

Fabien Castanié ◽

Laurent Nony ◽

Sébastien Gauthier ◽

Xavier Bouju

Keyword(s):

Molecular Dynamics ◽

Silicon Carbide ◽

Dynamic Systems ◽

Equilibrium Position ◽

Graphene Nanoribbons ◽

Atomic Scale ◽

Planar Substrate ◽

Silicon Carbide Substrate ◽

The Stability ◽

Good Agreement

Background: Characterization at the atomic scale is becoming an achievable task for FM-AFM users equipped, for example, with a qPlus sensor. Nevertheless, calculations are necessary to fully interpret experimental images in some specific cases. In this context, we developed a numerical AFM (n-AFM) able to be used in different modes and under different usage conditions. Results: Here, we tackled FM-AFM image calculations of three types of graphitic structures, namely a graphite surface, a graphene sheet on a silicon carbide substrate with a Si-terminated surface, and finally, a graphene nanoribbon. We compared static structures, meaning that all the tip and sample atoms are kept frozen in their equilibrium position, with dynamic systems, obtained with a molecular dynamics module allowing all the atoms to move freely during the probe oscillations. Conclusion: We found a very good agreement with experimental graphite and graphene images. The imaging process for the deposited nanoribbon demonstrates the stability of our n-AFM to image a non-perfectly planar substrate exhibiting a geometrical step as well as a material step.

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First‐Principles Molecular Dynamics Study of the Threshold Displacement Energy in LiFe 5 O 8

Crystal Research and Technology ◽

10.1002/crat.202100076 ◽

2021 ◽

pp. 2100076

Author(s):

Shijie Tan ◽

Wei Zhang ◽

Feng Jiao ◽

Yongchuan Zhou ◽

Lu Yang ◽

...

Keyword(s):

Molecular Dynamics ◽

First Principles ◽

Displacement Energy ◽

Threshold Displacement ◽

First Principles Molecular Dynamics

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Molecular dynamics simulation model for the quantitative assessment of tool wear during single point diamond turning of cubic silicon carbide

Computational Materials Science ◽

10.1016/j.commatsci.2011.07.052 ◽

2012 ◽

Vol 51 (1) ◽

pp. 402-408 ◽

Cited By ~ 69

Author(s):

Saurav Goel ◽

Xichun Luo ◽

Robert L. Reuben

Keyword(s):

Molecular Dynamics ◽

Silicon Carbide ◽

Molecular Dynamics Simulation ◽

Tool Wear ◽

Simulation Model ◽

Quantitative Assessment ◽

Single Point ◽

Diamond Turning ◽

Dynamics Simulation ◽

Cubic Silicon Carbide

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Reveal the fast and charge-insensitive lattice diffusion of silver in cubic silicon carbide via first-principles calculations

Computational Materials Science ◽

10.1016/j.commatsci.2019.109190 ◽

2019 ◽

Vol 170 ◽

pp. 109190 ◽

Cited By ~ 3

Author(s):

Qing Peng ◽

Nanjun Chen ◽

Zhijie Jiao ◽

Isabella J. van Rooyen ◽

William F. Skerjanc ◽

...

Keyword(s):

Silicon Carbide ◽

First Principles ◽

Lattice Diffusion ◽

First Principles Calculations ◽

Cubic Silicon Carbide

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Atomic-Scale Modeling of the Annihilation of Jogged Screw Dislocation Dipoles

MRS Proceedings ◽

10.1557/proc-578-217 ◽

1999 ◽

Vol 578 ◽

Cited By ~ 7

Author(s):

T. Vegge ◽

O. B. Pedersen ◽

T. Leffers ◽

K. W. Jacobsen

Keyword(s):

Molecular Dynamics ◽

Screw Dislocation ◽

Atomic Scale ◽

Atomistic Simulations ◽

Elastic Band ◽

Screw Dislocations ◽

Scale Modeling ◽

Band Method

AbstractUsing atomistic simulations we investigate the annihilation of screw dislocation dipoles in Cu. In particular we determine the influence of jogs on the annihilation barrier for screw dislocation dipoles. The simulations involve energy minimizations, molecular dynamics, and the Nudged Elastic Band method. We find that jogs on screw dislocations substantially reduce the annihilation barrier, hence leading to an increase in the minimum stable dipole height.

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The influence of palladium impurities on vacancy diffusion in cubic silicon carbide

MRS Proceedings ◽

10.1557/proc-1264-bb06-03 ◽

2010 ◽

Vol 1264 ◽

Author(s):

Guido Roma

Keyword(s):

Silicon Carbide ◽

First Principles ◽

Kinetic Properties ◽

Vacancy Diffusion ◽

First Principles Calculations ◽

Low Concentrations ◽

Diffusion Mechanisms ◽

Cubic Silicon Carbide ◽

As Solubility ◽

Correlation Factors

AbstractThe basic properties of palladium impurities in silicon carbide, such as solubility or diffusion mechanisms, are far from being well understood. In a recent paper I presented a systematic study of stability and kinetic properties of Pd in cubic silicon carbide using first principles calculations. In this paper I focus on the effect of the presence of palladium in silicon carbide, even in very low concentrations, on the kinetic properties of carbon vacancies. I apply a odel of Pd diffusion through a vacancy mechanism on the carbon sublattice and extract the correlation factors leading to an enhancement of vacancy migration, due to the coupling of iffusion fluxes between vacancies and palladium impurities.

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