The Prolific { ZR 6 } X 12 R and { ZR 6 } X 10 Structure Types with Isolated Endohedrally Stabilized ( Z ) Rare‐Earth Metal ( R ) Cluster Halide ( X ) Complexes

Comproportionation reactions of rare‐earth metal trihalides, RX 3 , with the respective R metal in the presence of a transition metal Z , preferably from group 8 through 10, yielded single crystals of 31 { ZR 6 } X 12 R and 22 { ZR 6 } X 10 type compounds, in most cases for the first time, especially with R = Tb, Dy, Ho, and Er. These are compared with literature entries. The crystal structures are discussed for the equal‐atom pair {IrEr 6 }I 12 Er and {IrEr 6 }I 10 . In both cases, {IrEr 6 }I i 12 I a 6 cluster complexes are connected via i‐i and i‐a/a‐i bridges, respectively, the {IrEr 6 } clusters are isolated. Band structure calculations were carried out on the LMTO‐ASA level for a number of { Z Y 6 } X 10 examples; the density of states (DOS) and Crystal Orbital Hamiltonian Populations (COHP) derived therefrom exhibit strong Z– Y and Y –X bonding interactions. Most profitable are X = I and endohedral elements of sixth period atoms, especially Z = Os, Ir.