EFFECTIVE POTENTIAL FOR ADSORPTION

A solution is proposed to the standing problem of the derivation of a wall-interface potential V(GAMMA) as a function of the adsorption GAMMA. A stringent upper bound to v(GAMMA) is obtained in the course of minimizing the surface free-energy functional gamma[m]BAR, keeping GAMMA constant, within the space of continuous and differentiable profiles m (z). Comparison of V(GAMMA) with available alternative potentials V(1), l being the wall-interface separation, indicates potentially important implications for critical wetting theory in three dimensions. The availability of V(GAMMA), furthermore, leads to improved interface displacement models of three-phase contact lines.