Structure prediction and energy landscape exploration in the zinc oxide system

The rational planning of syntheses, i.e. the search for new crystalline compounds followed by their synthesis is a central topic of solid state chemistry. In order to gain new insights in the ZnO system, we have performed global explorations of the energy landscape using simulated annealing with an empirical potential, both at standard and elevated pressure (up to 100 GPa). Besides the well-known structure types (wurtzite, sphalerite and rock-salt), many new interesting modifications were found in different regions of the energy landscape, e.g. the “5-5” type, the NiAs type, and the β-BeO type. Furthermore, we observed many distorted variations of these main types, in particular new structures built-up from various combinations of structure elements of these types, exhibiting a variety of stacking orders.