Phase diagram and free energies of vapor films and tubes for a confined fluid

When confined between two parallel drying surfaces that are separated by a small distance, D, a liquid close to liquid-gas coexistence becomes metastable and evaporates. This paper focuses on this surface-induced phase transition. With mean field theory, we describe the pertinent phases and the corresponding density profiles for a lattice gas model. In one of the three phases, vapor films form between the liquid and the drying surfaces. Analytical estimates and Monte Carlo simulations indicated that the pathway to evaporation involves the concerted action of high-amplitude fluctuations of the vapor-film interfaces and the formation of vapor tubes that bridge these interfaces.