Multilayer adsorption on a fractally rough surface

Abstract

Models are proposed for thick-film-coverage adsorption on a general fractal surface. The basic idea is that long-range dispersion forces dominate the thermodynamic behavior. The analysis predicts the coverage to be proportional to [ln(${P}_{0}$/P${)]}^{(D\mathrm{\ensuremath{-}}3)/3}$ where P/${P}_{0}$ is the relative vapor pressure and D is the fractal dimension of the surface. Experimental examples for this behavior are presented. They are rough Ag surfaces, giving D=2.30. .AE