1. Introduction

The last few years have been marked by striking experimental results concerning some of the basic building blocks fundamental to nanoscience. Nano-objects such as carbon nanotubes and semiconductor nanowires have continued to provide many surprises, while a new material, graphene, has been synthesized. The exploration of nanoscience is made possible by fine characterization techniques such as near-field microscopy (STM: Scanning Tunneling Microscopy, AFM: Atomic Force Microscopy, etc.). However, the analysis of atomic surface reconstructions, deposited organic or inorganic nanostructures, and supramolecular self-assemblies cannot be carried out properly without a simulation tool...