In general terms, understanding and mastering the physics and chemistry of
adsorption processes at nanostructures and surfaces is a basic requirement
for the full development of nanoscience and nano-technology.
Metal surfaces are effective chemical agents capable of adsorbing and/or
dissociating molecules impinging from the gas phase. Industrial processes
of enormous economical impact, such as corrosion and heterogeneous catalysis,
greatly benefit from recent developments in basic research on this matter.
Over the last years, the combination of experimental molecular-beam techniques
and refined theoretical calculations based on ab-initio methods have
led research on the field to a new stage, in which detailed investigations
of the kinetics and dynamics of molecular reactivity at surfaces are possible.
In the "Gas/Solid Interfaces" group, we are mainly interested in the elementary reactive processes that may happen whenever atoms or small molecules interact with surfaces. When a molecule approaches the surface, intramolecular chemical bonds can break down and new ones be formed with the surface. We use first-principles electronic structure calculations to describe the details of the interaction between the incoming species and the surface through a multidimensional potential energy surface (PES). Once the PES of the system is known, we simulate the dynamics of several processes by solving the classical equations of motion of the nuclei.
We pay particular attention to the non-adiabatic processes and the energy dissipation channels that come into play, because they can drastically change the output of the dynamics. From a theoretical point of view, the description of ground state properties is currently well founded and has proven to be extremely successful in explaining elementary reactive and non-reactive adiabatic processes at surfaces. The description of excited states and the evaluation of energy transfer mechanisms is however still maturing and further developments are needed to reach the same level of detail in the understanding and of accuracy in the quantitative representation.