Spontaneous Capillary-Inertial Dewetting at the Microscopic Scale

We resolve the dewetting dynamics of water films on partially wetting surfaces at the microscopic scale and highlight its distinctions from liquid wetting. Fast dewetting occurring at the millisecond scale is dominated by capillary and inertial forces, obeying a power law with a wettability-independent exponent, which is different from the capillary-inertial dynamic wetting. Molecular-level inspections of moving contact lines further reveal that liquid molecules retract from solid surfaces through a rolling motion, whereas dynamic wetting proceeds mainly with the sliding motion. These distinct hydrodynamic behaviors and molecular kinetics explicitly suggest that dynamic dewetting is not simply the reverse of dynamic wetting, which has significant implications for interfacial fluid physics.