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Surface Wetting of Liquid Nanodroplets

David R. Heine·Gary S. Grest·Edmund B. Webb III
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Abstract

The spreading of liquid nanodroplets of different initial radii $R_{0}$ is studied using molecular dynamics simulation. Results for two distinct systems, Pb on Cu(111), which is non-wetting, and a coarse grained polymer model, which wets the surface, are presented for Pb droplets ranging in size from $\sim55 000$ to $220 000$ atoms and polymer droplets ranging in size from $\sim200 000$ to $780 000$ monomers. In both cases, a precursor foot precedes the spreading of the main droplet. This precursor foot spreads as $r_{f}^{2}(t)=2D_{eff}t$ with an effective diffusion constant that exhibits a droplet size dependence $D_{eff}\sim R_{0}^{1/2}$. The radius of the main droplet $r_{b}(t)\sim R_{0}^{4/5}$ in agreement with kinetic models for the cylindrical geometry studied.

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David R. Heine, Gary S. Grest, Edmund B. Webb III. 2005-05-05. Surface Wetting of Liquid Nanodroplets. https://arxiv.org/abs/cond-mat/0410215

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