Collective surface diffusion near a first-order phase transition

Igor Medved'; Anton Trník

doi:10.1103/physrevb.83.233406

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arXiv · 1104.4388

Collective surface diffusion near a first-order phase transition

Igor Medved'·Anton Trník

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Abstract

For a large class of lattice models we study the thermodynamic factor, $Φ$, of the collective surface diffusion coefficient near a first-order phase transition between two phases at low temperatures. In a two-phase regime its dependence on the coverage, $\te$, is $Φ\approx \te/[(\te-\te_-)(\te_+ - \te)N]$, where $N$ is the number of adsorption sites and $\te_\pm$ are the single-phase coverages at the transition. In the crossover between the two-phase and single-phase regimes $Φ(\te)$ is shown to have a more complex behavior. The results are applied to a simple 2D lattice model.

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BibTeX RIS

Igor Medved', Anton Trník. 2011-04-22. Collective surface diffusion near a first-order phase transition. https://doi.org/10.1103/physrevb.83.233406

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