Hydrogen Diffusion in Silicon from Tight-Binding Molecular Dynamics

ABSTRACTTight-binding molecular dynamics calculations reveal a new mechanism for hydrogen diffusion in hydrogenated amorphous silicon. Hydrogen diffuses through the network by successively bonding with nearby silicon and breaking their Si-Si bonds. The diffusing hydrogen carries with it a newly created dangling bond. These intermediate transporting states are densely populated in the network and have lower energies than H at the center of stretched Si-Si bonds.

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Impact of vibronic coupling effects on light-driven charge transfer in pyrene-functionalized middle and large-sized Metalloid Gold Nanoclusters from Ehrenfest dynamics.

Physical Chemistry Chemical Physics ◽

10.1039/d1cp02890a ◽

2021 ◽

Author(s):

Adrian Dominguez-Castro ◽

Thomas Frauenheim

Keyword(s):

Molecular Dynamics ◽

Charge Transfer ◽

Density Functional ◽

Theoretical Calculations ◽

Gold Nanoclusters ◽

Tight Binding ◽

Time Dependent ◽

Effective Strategy ◽

Dynamics Simulations ◽

Dependent Density

Theoretical calculations are an effective strategy to comple- ment and understand experimental results in atomistic detail. Ehrenfest molecular dynamics simulations based on the real-time time-dependent density functional tight-binding (RT-TDDFTB) approach...

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Diamond {111} Surface: Graphitization or Reconstruction?

MRS Proceedings ◽

10.1557/proc-383-349 ◽

1995 ◽

Vol 383 ◽

Cited By ~ 2

Author(s):

G. Jungnickel ◽

D. Porezag ◽

Th. Frauenheim ◽

W. R. L. Lambrecht ◽

B. Segall ◽

...

Keyword(s):

Molecular Dynamics ◽

Density Functional Theory ◽

Density Functional ◽

Tight Binding ◽

Diamond Growth ◽

Functional Theory ◽

Surface Phases ◽

Surface Graphitization

ABSTRACTThe reconstruction of the diamond {1111} surface is re-examined by means of density functional theory based tight-binding molecular dynamics. Evidence is found for competition between a graphitizing tendency leading to an unreconstructed but relaxed 1 × 1 surface and a π-bonded chain-like 2 × 1 reconstruction. The implications of the possible co-existence of these two distinct surface phases for diamond growth are discussed.

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Nickel-related defect in diamond: A tight-binding molecular-dynamics study

Computational Materials Science ◽

10.1016/j.commatsci.2006.06.003 ◽

2007 ◽

Vol 38 (4) ◽

pp. 873-882 ◽

Cited By ~ 1

Author(s):

Kenji Tsuruta ◽

Satoshi Emoto ◽

Chieko Totsuji ◽

Hiroo Totsuji

Keyword(s):

Molecular Dynamics ◽

Tight Binding ◽

Related Defect

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Tight-Binding Molecular Dynamics Simulations on Point Defects Diffusion and Interactions in Crystalline Silicon

MRS Proceedings ◽

10.1557/proc-396-33 ◽

1995 ◽

Vol 396 ◽

Cited By ~ 3

Author(s):

M. tang ◽

L. colombo ◽

T. Diaz De La Rubia

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulations ◽

Point Defects ◽

Crystalline Silicon ◽

Tight Binding ◽

Diffusion Path ◽

Binding Energies ◽

Defect Clusters ◽

Dynamics Simulations

AbstractTight-binding molecular dynamics (TBMD) simulations are performed (i) to evaluate the formation and binding energies of point defects and defect clusters, (ii) to compute the diffusivity of self-interstitial and vacancy in crystalline silicon, and (iii) to characterize the diffusion path and mechanism at the atomistic level. In addition, the interaction between individual defects and their clustering is investigated.

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Statistically averaged molecular dynamics simulations of hydrogen diffusion in magnesium and magnesium hydrides

Physical Review Materials ◽

10.1103/physrevmaterials.4.105401 ◽

2020 ◽

Vol 4 (10) ◽

Author(s):

C. D. Spataru ◽

T. W. Heo ◽

B. C. Wood ◽

V. Stavila ◽

S. Kang ◽

...

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulations ◽

Hydrogen Diffusion ◽

Dynamics Simulations ◽

Magnesium Hydrides

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Mechanisms and kinetics of initial pyrolysis and combustion reactions of 1,1-diamino-2,2-dinitroethylene from density functional tight-binding molecular dynamics simulations

Canadian Journal of Chemistry ◽

10.1139/cjc-2019-0141 ◽

2019 ◽

Vol 97 (11) ◽

pp. 795-804 ◽

Cited By ~ 1

Author(s):

Dong Xiang ◽

Weihua Zhu

Keyword(s):

Activation Energy ◽

Molecular Dynamics ◽

Density Functional ◽

Tight Binding ◽

Combustion Process ◽

Exponential Factor ◽

Three Stages ◽

Dynamics Simulations ◽

Combustion Processes ◽

Kinetics Of

The density functional tight-binding molecular dynamics approach was used to study the mechanisms and kinetics of initial pyrolysis and combustion reactions of isolated and multi-molecular FOX-7. Based on the thermal cleavage of bridge bonds, the pyrolysis process of FOX-7 can be divided into three stages. However, the combustion process can be divided into five decomposition stages, which is much more complex than the pyrolysis reactions. The vibrations in the mean temperature contain nodes signifying the formation of new products and thereby the transitions between the various stages in the pyrolysis and combustion processes. Activation energy and pre-exponential factor for the pyrolysis and combustion reactions of FOX-7 were obtained from the kinetic analysis. It is found that the activation energy of its pyrolysis and combustion reactions are very low, making both take place fast. Our simulations provide the first atomic-level look at the full dynamics of the complicated pyrolysis and combustion process of FOX-7.

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