ABSTRACT
Before investigating the consequences of the presence of line tension on the wetting transition, we first discuss the physical origin of the magnitude of the line tension. Just as the surface tension originates from the interaction between molecules, the magnitude of the line tension is determined by the interaction between the molecules and the substrate [22]. This interaction can be described by the surface potential, V(l), which is the integrated interaction energy between a liquid layer with thickness l and the substrate. In general V(l) exhibits a strong repulsion at short distances, a minimum at some characteristic distance lmin, and decays to its asymptotic value at large distances (see Fig. 14). The value of the interaction potential at the equilibrium thickness, l=lmin, is the surface tension of the partially wetted substrate, V(lmin)=σsv, while the surface potential at l=∞ is equal to the surface
