Adsorption of supercritical carbondioxide on to silica gel . How /do I creat a model for the silica with known number of pores and number of atoms(if possible pore volume). How can I know where to attach the carbon dioxide molecules (and the number of the carbon molecules(per number of pore or per number of atoms of the silica gel cell) to attach) to the the constructed silica gel cell. How do I proceed. Thanks a lot for your contribution.