Atomic-Environment Classification of the Cubic "Intermetallic" Structures Types

A complete description of the geometrical atomic environments found in the structure types of the cubic intermetallic compounds is given. Analysis of 172 structures types which have been reported in the literature showed that 128 are geometrically possible, while the remaining 44 structure types have improbable interatomic distances. All point sets of these structure types are classified in terms of the realized geometrical atomic environments and rules are given for the analysis and the classification. In systematic and comprehensive analysis of the cubic structure types, all known relationships between these structures types were verified, but the analysis also revealed new non-trivial relationships. In addition, 21 atomic environment types are strongly preferred. Out of 13 917 point sets investigated, 12 790 (92%) belong to one of those 21 atomic environment types. Of the 5521 compounds crystallizing into one of the 128 structure types, 46% belong to a single-environment group (structures in which all atoms have the same type of environment), 37% combine two environment types, 9% have three environments and the rest (8%) have four or more environments.