Cluster Self-Organization of Intermetallic Systems. New Cluster Presursor (InNa5)(AuAu5) and Primary Chain with the 5m Symmetry for the Self-Assembly of the Na32Au44In24–oP100 Crystal Structure

详细

The combinatorial-topological analysis and simulation of the self-assembly of the Na₃₂Au₄₄In₂₄–oP100 (space group P bcm, a = 5.483 Å, b = 24.519 Å, c = 14.573 Å, V = 1895 ų) crystal structure are conducted by the computer-based methods (TOPOS program package). A new type of the 12-atom K12 cluster formed from doubled pentagonal pyramids—AuAu₅ and InNa₅—is established. The maximal symmetry of the K12 cluster and the primary chain of translationally bound K12 clusters correspond to the noncrystallographic 5m symmetry. The symmetry and topological codes of the Na₃₂Au₄₄In₂₄–oP100 3D structure’s self-assembly processes from the K12 nanocluster precursors are reconstructed in the following form: primary chain → microlayer → micro-framework. The primary chains of bound K12 clusters with the m symmetry are located in the direction [100], and the distance between cluster centers determines the vector’s value: a = 5.483 Å. There are four nonparallel primary chains in the primary chain’s local environment. The chains from InAu atoms and NaAu₂In₂ clusters are located in the 2D layer between the primary chains. The distance between the equivalent chains in the direction [001] determined the vector’s value: c = 14.573 Å. In the 3D framework in the direction [010], the distance between the equivalent 2D layers determined the vector’s value: b = 24.519 Å.