The cosine law at the atomic scale: Toward realistic simulations of Knudsen diffusion

Franck Celestini; Fabrice Mortessagne

doi:10.1103/physreve.77.021202

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arXiv · 0708.1117

The cosine law at the atomic scale: Toward realistic simulations of Knudsen diffusion

Franck Celestini·Fabrice Mortessagne

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Abstract

We propose to revisit the diffusion of atoms in the Knudsen regime in terms of a complex dynamical reflection process. By means of molecular dynamics simulation we emphasize the asymptotic nature of the cosine law of reflection at the atomic scale, and carefully analyze the resulting strong correlations in the reflection events. A dynamical interpretation of the accomodation coefficient associated to the slip at the wall interface is also proposed. Finally, we show that the first two moments of the stochastic process of reflection non uniformly depend on the incident angle.

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BibTeX RIS

Franck Celestini, Fabrice Mortessagne. 2007-08-08. The cosine law at the atomic scale: Toward realistic simulations of Knudsen diffusion. https://doi.org/10.1103/physreve.77.021202

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