Structure characterization and predictability by Voronoi analysis

The unique ability of tessellation methods to characterize atomic structure s is highlighted, with the Voronoi tessellation, by virtue of its freedom f rom constraining assumptions, emphasized as pre-eminent among these methods . It is demonstrated how to extract information from an atomic structure by constructing its Voronoi tessellation and analysing the results. In so doi ng, insight is gained into the coordination patterns of the atoms and how t heir positions are influenced by neighbours. As an example of such a proced ure, typical Voronoi volumes are calculated for 72 atom types found in a se t of 249 binary intermetallic and ionic compounds. Whereas the various atom types have broadly characteristic volumes, these are also sensitive to the other atom types with which they are combined in a given compound, i.e. wh ether the latter behaves as a metal, semimetal, semiconductor or insulator. Further, smaller variations in volume occur for different atom types withi n these four categories. Thus, structural information obtained from the Vor onoi tessellation may possibly be correlated directly with atomic propertie s.