γ‑Brass Polyhedral Core in Intermetallics: The Nanocluster Model

Using
the TOPOS program package, 26-atom nanoclusters of the γ-brass
(Cu5Zn8) type (0@4@22 or 0@8@18) were found
in 5918 crystal structures of cubic intermetallics. The nanocluster
models were built for all the intermetallics using a recently developed
algorithm implemented into TOPOS. The relations of the structures
based on the 0@4@22 core are explored as a result of migration of
atoms between different shells of the nanoclusters. It is shown that
the 0@4@22 nanoclusters frequently occur as building units of intermetallics
of different composition and structure type. Regularities in chemical
composition of 702 γ-brass-type nanoclusters were found within
both the nanoclusters approach (multishell structure) and the nested-polyhedra
model. A database containing all topological types of γ-brass
nanoclusters is created with which one can search for the corresponding
atomic configuration in any intermetallics.