Influence of the heterogeneities of the solid on the surface diffusion of adsorbed gases

A model for the surface diffusion of adsorbed gases on porous solids is proposed. In it the heterogeneities of the solid and its influence on the diffusion coefficient are taken into account. The results obtained with the model are compared with new experimental data. A satisfactory agreement in covering ranges which run from very low values to the monolayer is achieved. The values of the parameters involved are found to be very reasonable.