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arXiv · 1504.00379

Ice Nucleation on Carbon Surface Supports the Classical Theory for Heterogeneous Nucleation

Abstract

The prevalence of heterogeneous nucleation in nature was explained qualitatively by the classical theory for heterogeneous nucleation established over more than 60 years ago, but the quantitative validity and the key conclusions of the theory have remained unconfirmed. Employing the forward flux sampling method and the coarse-grained water model mW, we explicitly computed the heterogeneous ice nucleation rates in the supercooled water on a graphitic surface at various temperatures. The independently calculated ice nucleation rates were found to fit well according to the classical theory for heterogeneous nucleation. The fitting procedure further yields the estimate of the potency factor which measures the ratio of the heterogeneous nucleation barrier to the homogeneous nucleation barrier. Remarkably, the estimated potency factor agrees quantitatively with the volumetric ratio of the critical nuclei between the heterogeneous and homogeneous nucleation. Our numerical study thus provides a strong support to the quantitative power of the theory, and allows understanding ice nucleation behaviors under the most relevant freezing conditions.

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Raffaela Cabriolu, Tianshu Li. 2015-04-06. Ice Nucleation on Carbon Surface Supports the Classical Theory for Heterogeneous Nucleation. https://doi.org/10.1103/physreve.91.052402

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