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This is the second of two papers, where we discuss the cluster structures of a novel family of cluster-based intermetallic phases of unprecedented complexity: cF444-Al63.6Ta36.4 (AT-19), a = 19.1663 (1) Å, V = 7040 Å3, cF(5928 − x)-Al56.6Cu3.9Ta39.5, x = 20 (ACT-45), a = 45.376 (1) Å, V = 93 428 Å3 and cF(23, 256 − x)-Al55.4Cu5.4Ta39.1, x = 122 (ACT-71), a = 71.490 (4) Å, V = 365 372 Å3. The space group is 
in all three cases. The structures can be described as packings of clusters such as fullerenes, dodecahedra, pentagonal bifrusta and Friauf polyhedra. A characteristic feature of the two larger structures are nets of hexagonal bipyramidal Ta clusters (h.b.p.). The extremely short distance of 2.536–2.562 Å between their apical Ta atoms indicates unusually strong bonding. The large h.b.p. nets are sandwiched between slabs of Friauf polyhedra resembling the structure of the μ phase.
in all three cases. The structures can be described as packings of clusters such as fullerenes, dodecahedra, pentagonal bifrusta and Friauf polyhedra. A characteristic feature of the two larger structures are nets of hexagonal bipyramidal Ta clusters (h.b.p.). The extremely short distance of 2.536–2.562 Å between their apical Ta atoms indicates unusually strong bonding. The large h.b.p. nets are sandwiched between slabs of Friauf polyhedra resembling the structure of the μ phase.
