Solids comprising three-dimensional networks of mainly p-elements are currently intensely investigated in the context of new materials revealing novel combinations of physical characteristics. By application of high hydrostatic pressures, the topology of covalent element structures can be modified often yielding new and unusual structural and physical properties. In binary compounds, the specific interaction between anionic network and cationic filler atoms provides another degree of freedom to tailor the material features by variation of the constituting elements.
We are extensively investigating the performance of high-pressure high-temperature synthesis in stabilizing unusual atomic patterns. Recent experiments have demonstrated that elevated pressure is a suitable means to prepare new metastable element modifications or binary compounds. The characterization of the yielded phases with respect to their thermal stability at ambient conditions provides access to even more atomic patterns with hitherto unknown composition or crystal structure.