Understanding the reactivity of metallic nanoparticles: beyond the extended surface model for catalysis.

Metallic nanoparticles (NPs) constitute a new class of chemical objects which are used in different fields as diverse as plasmonics, optics, catalysis, or biochemistry. The atomic structure of the NP and its size usually determine the chemical reactivity but this is often masked by the presence of capping agents, solvents, or supports. The knowledge of the structure and reactivity of isolated NPs is a requirement when aiming at designing NPs with a well-defined chemistry. Theoretical models together with efficient computational chemistry algorithms and parallel computer codes offer the opportunity to explore the chemistry of these interesting objects and to understand the effects of parameters such as size, shape and composition allowing one to derive some general trends.