Wetting is a widespread phenomenon, most prominent in a number of cases, bothin nature and technology. Droplets of pure water with initial radius rangingfrom 20 to 80 [\AA] spreading on graphitic surfaces are studied by moleculardynamics simulations. The equilibrium contact angle is determined and thetransition to the macroscopic limit is discussed using Young equation in itsmodified form. While the largest droplets are almost perfectly spherical, theprofiles of the smallest ones are no more properly described by a circle. Forthe sake of accuracy, we employ a more general fitting procedure based on localaverages. Furthermore, our results reveal that there is a possible transitionto the macroscopic limit. The modified Young equation is particularly precisefor characteristic lengths (radii and contact-line curvatures) around 40 [\AA].
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