Contact Angle Relaxation during Droplet Spreading:  Comparison between Molecular Kinetic Theory and Molecular Dynamics

The macroscopic behavior of the contact line during the spontaneous spreading of a droplet can be described in terms of microscopic quantities, specifically the substrate−liquid and liquid−liquid interactions. Here, for the first time, the results of molecular dynamics simulations of very large sessile drop systems are compared with the predictions of the molecular−kinetic theory of wetting. Good agreement is obtained, with both approaches yielding a consistent set of molecular parameters and macroscopic behavior which is consistent with experiments.