“…By decomposing the free energy of a droplet on a solid substrate into volume, interfacial, and line contributions, we can theoretically determine the intrinsic line tension. Since the liquid-vapor surface is curved and interfacial zone is diffuse, there is a conceptual problem of dividing surface [3,22,[24][25][26]. Therefore, instead of directly analyzing a cap-shaped droplet with a finite base radius and a spherical meniscus, a liquid wedge with a flat meniscus, which corresponds to the limit of infinite base radius, is usually considered.…”