Concept of the Supporting Substructure in Intermetallics: V, Nb, and Ta Binary Compounds and Alloys

A novel approach to the modeling and analysis of crystal structures of binary intermetallic compounds is proposed, which is based on the concept of a supporting substructure (supporting net). We represent crystal structures of intermetallics as three-periodic atomic nets in which a component (three-periodic subnet) consisting of metal atoms of the same type is selected. Atoms of the other metal are considered to occupy cages in the substructure; the cages are modeled as the natural tiles constructed from the supporting net according to a strict algorithm. We have shown that many supporting substructures are topologically related to the structures of the elemental metals. This means that the structure of many intermetallic compounds can be treated like alloys as a result of the substitution of some atoms of elemental metal with the atoms of another metal. The difference from alloys is that in an intermetallic compound, a regular part of the structure of one metal is substituted, not random separate atoms. Based on the proposed approach, we have explored 570 V-, Nb-, or Ta-containing binary intermetallics. A number of structural relations between metals and intermetallic compounds have been revealed, and possible applications for modeling hypothetical intermetallic structures have been discussed.