The Lotus effect at the nanometer scale: Capillary evaporation in rectangular nonwettable grooves

We employ Monte Carlo simulations in the grand canonical ensemble to investigate sorption of a “simple” fluid (i.e., a fluid in which molecules possess only translational degrees of freedom) between two solid surfaces endowed with a periodic sequence of rectangular, nanoscopic grooves. The fluid–substrate interaction is purely repulsive such that the substrate cannot be wet by the fluid material. By varying the distance between the substrates we may control the physical nature of the portion of fluid outside the grooves. Depending on whether or not that fluid is in a gaseous or liquidlike state adsorption inside the groove may occur as a discontinuous or continuous process.