The study of the interaction between (large) molecules and inorganic (metal) surfaces is a typical multiscale problem. In fact while the specific chemistry emerges at the quantum scale with the interaction of the electrons of the surface with the valence electrons of the molecule, the molecular conformations are instead the expression of a large scale statistical behavior. The delicate interplay between these two aspects, intimately linked during the adsorption process, gives rise to the interface properties. I will show the application of a sequential modeling procedure which links the quantum to the classical atomistic scale in a consistent way. Within this framework the ideal approach would be to identify and use only those degrees of freedom strictly required by the problem. To achieve this goal I will illustrate the first step of the development of a spatially adaptive simulation scheme (AdResS) which allows to switch from the atomistic to a coarse-grained description on demand.