The fractal analysis of microporous solids through the molecular tiling method is dependent on the geometry and orientation of molecules in the adsorbed phase as well as the mechanism of adsorption (monolayer-multilayer coverage or micropore volume-filling) occurring in the pores. The data of Sermon et al. (9) obtained with a series of n-alkanes on a microporous silica sol-gel have been reanalyzed by taking into account the micropore volume-filling process as well as the linear nature of the molecules and their parallel-lying, nearest neighbor, chain configuration on the surfaces of the sol-gel.