Computational modeling of water/metal interfaces
The behavior of water at metal surfaces is important both from theoretical and practical points of view. The former because the understanding of the microscopic details of the associated electrochemical processes is necessary to improve this field. The latter due to the fact it has a key role in many applications of electrochemistry, e.g. in energy conversion and storage devices, corrosion and heterogeneous catalysis. Yet, experimental characterizations of the metal/aqueous interface have had many setbacks, leading to many unclear aspects. In this regard, atomistic simulations can complement the nanoscopic picture of this system, validating and predicting empirical data and also assisting in their interpretation. The best-case scenario would be performing a full ab initio molecular dynamics simulation to accurately describe the structural and dynamic properties of the interface. However, this is computationally too expensive. Hence the usual prototype systems have models restricted in terms of size and time. An alternative to bypass this hindrance is to carry out a hybrid QM/MM computational protocol. In this framework, a multi-scale approach to the water and metal interactions can be implemented, with quantum mechanics methods providing the reactivity of the surface in large scale simulations. By means of this method the interface of gold and water, influenced by the polarization effects of the metal due to the presence of water, was analyzed in the interest of developing a reliable polarizable force field to describe this water/metal interface.