| Theoretical methods such as virial expansion, mean field theory and Monte Carlo simulations are employed to investigate adsorption of gases on various surfaces. For complex substrates like quasicrystalline structures, a virial expansion approach provides adsorption isobars and isosteric heats which are compared to experimental data in the limit of low coverage. In the case of flat or weakly corrugated substrates, a two dimensional approximation of the virial expansion is used instead. Adsorption inside cylindrical pores, as found in carbon nanotube bundles, is explored with a lattice gas model evaluated with mean field and Monte Carlo techniques in both grand canonical and canonical ensembles. The phonon spectrum of a monolayer film adsorbed on the wall of a spherical surface is calculated and compared to that of a cylindrical film. A special attention in this thesis is dedicated to the effective dimensionality experienced by the adsorbate, which leads to new and interesting effects. |
