Liquid-vapor coexistence in a chemically heterogeneous slit-nanopore

A Lennard-Jonesium film confined between planar walls made of alternating strips of strongly and weakly adsorbing solid substrate was simulated by the grand canonical Monte Carlo method. When the walls are molecularly close, they serve as a nanoscale template, on which liquid bridging the gaps between the “strong” strips coexists with gas over the “weak” ones. The structure of the nanoscopic liquid-gas interface has the same form as that of the planar interface. When the walls become too far apart, the bridges give way to “nanodroplets” adhering to the strong strips coexisting with dilute gas.