Nanoclusters based on pentagondodecahedra with shells in the form of <Emphasis Type="Italic">D</Emphasis>32, <Emphasis Type="Italic">D</Emphasis>42, and <Emphasis Type="Italic">D</Emphasis>50 deltahedra in crystal structures of intermetallic compounds

The TOPOS software package has been used to form a database of intermetallic compounds containing pentagondodecahedral d clusters (528 crystal structures of intermetallic compounds, 111 topological types, and 47 space symmetry groups). On the whole, 606 atomic d configurations have been selected which are described by 14 point symmetry groups. Examples of nanoclusters are presented which are precursors of the crystal structures of intermetallic compounds with the outer shell in the form of deltahedra D, which are formed above dodecahedra. These nanoclusters are identified in the automatic mode of structural data processing: D32 (K₈In₆Ge₄₀, Cs₃₀Na₃Sn₁₆₂), D ₄₂ (Ru₃Be₁₇, Y₃Cd₁₈, Ca₃(Cd₁₇Al)), and D ₅₀ (Yb₃Zn₁₈, Ce₃(Au₁₄Sn₃), Pr₃Cd₁₈, Eu₄Cd₂₅), where 32, 42, and 50 are the numbers of atoms in the shell. Similar deltahedra were found previously in icosahedral nanoclusters (precursors of intermetallic compounds). Structures with the dodecahedral nanocluster precursors containing D42 and D50 deltahedra are approximants of MCd_5.7 (M = Yb or Ca) quasicrystals and belong to the family of MCd₆ (M = Ce, Pr, Nd, Sm, Eu, Gd, Dy, Yb, Y, or Ca).