Calculating constants of the rates of the reactions of excitation, ionization, and atomic exchange: A model of a shock oscillator with a change of the Hamiltonian of the system

Titanium carbides were studied via molecular dynamics simulation to characterize TiC[Formula: see text] structures with respect to the carbon diffusion properties in this study. The effect of carbon concentration on atomic structures of titanium carbides was investigated through discussing the structure variation and the radial distribution functions of carbon atoms in titanium carbides. The carbon diffusion in titanium carbides was also analyzed, focusing on the dependence on carbon concentration and carbide structure. Carbon diffusivity with different carbon concentrations was determined by molecular dynamics (MD) calculations and compared with the available experimental data. The simulation results showed an atomic exchange mechanism for carbon diffusion in titanium carbide.

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Vacancy Mediated Diffusion at Surface-Confined Atomic Intermixing

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.159.121 ◽

2010 ◽

Vol 159 ◽

pp. 121-124 ◽

Cited By ~ 2

Author(s):

Michail Michailov

Keyword(s):

Strain Energy ◽

Crystal Surface ◽

Adsorbed Layer ◽

Surface Pattern ◽

Spontaneous Generation ◽

Crystal Surfaces ◽

Adsorbed Atoms ◽

Atomic Exchange ◽

Surface Domains ◽

Experimental Findings

The present study deals with diffusion behavior of adsorbed atoms on stepped crystal surfaces. In volume-immiscible systems, two-dimensional (2D) atomic intermixing at epitaxial interface could be completely blocked on step-free surface domains. This is a result of high diffusion barrier for direct atomic exchange between adsorbed layer and substrate. In that case, diffusion takes place exclusively across the steps of atomic terraces. In such systems, dynamic competition between energy gain by mixing and substrate strain energy results in diffusion scenario where adsorbed atoms form alloyed stripes in the vicinity of terrace edges. At high temperatures, the stripe width increases and finally completely destroys the terraces. This process leads to formation of alloyed 2D atomic islands on top of pure substrate layer. The atomistic Monte Carlo simulations reveal vacancy-mediated mechanism of diffusion inside atomic terraces as a result of spontaneous generation of vacancies at high temperature. Being in agreement with recent experimental findings, the observed surface-confined alloying opens up a way various surface pattern to be configured at different atomic levels on the crystal surface.

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Some Observations on Atomic Exchange in NO

The Journal of Chemical Physics ◽

10.1063/1.1730973 ◽

1960 ◽

Vol 32 (5) ◽

pp. 1579-1581 ◽

Cited By ~ 5

Author(s):

W. Spindel ◽

Marvin J. Stern

Keyword(s):

Atomic Exchange

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CATION ANTISITE DEFECTS AND ANTISITE-BASED-DEFECT COMPLEXES IN GaAs

Modern Physics Letters B ◽

10.1142/s0217984990001422 ◽

1990 ◽

Vol 04 (18) ◽

pp. 1133-1136

Author(s):

S.B. ZHANG

Keyword(s):

Structural Change ◽

Fermi Level ◽

Valence Band ◽

Valence Band Maximum ◽

Recent Theory ◽

Band Maximum ◽

Defect Complexes ◽

Atomic Exchange ◽

Antisite Defects

Recent theory predicted that the Ga and B antisites in GaAs are bistable. As the Fermi level is lowered towards the valence-band maximum, a structural change from fourfold to threefold coordination will occur. The Ga antisite will undergo an atomic exchange in the presence of an As interstitial.

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