Surface tension of fluids with long range interactions

Abstract

Surface tension is a key physical property that quantifies the energy required to maintain an interface between two distinct phases. It plays a vital role in various scientifically and technologically significant processes, such as the nucleation of liquid droplets and the formation and collapse of bubbles. Theoretical studies suggest that for systems of molecules with long-range attractions, surface tension and its curvature corrections might not be well defined. In this work, a Monte Carlo simulation has been implemented to evaluate the planar surface tension of a Mie fluid with different attractive exponents. We have validated the simulation code for the particular case of the Lennard-Jones fluid, where we find values of the planar surface tension in perfect agreement with previous results from the literature at all temperatures. In the case of the Mie fluid, we find that the planar surface tension increases significantly as the range of the attractive interactions increases, while the width of the interface becomes progressively sharper. The influence of finite-size effects has also been analyzed, finding no significant effects. The study sets a reference value for planar surface tension as a starting point to analyze curvature effects, which might have important consequences in the nucleation behavior of fluids with long-range interactions