The Al 50 Cp* 12 Cluster – A 138‐Electron Closed Shell ( L = 6) Superatom

Metal clusters stabilized by a surface ligand shell represent an interesting intermediate state of matter between molecular metal-ligand complexes and bulk metal. Such "metalloid" clusters are characterized by the balance between metal-metal bonds in the core and metal-ligand bonds at the exterior of the cluster. In previous studies, the electronic stability for the Al50Cp*(12) cluster was not fully understood. We show here that the known cluster Al50Cp*(12) can be considered as an analogue to a giant atom ("superatom") with 138 sp electrons organized in concentric angular momentum shells up to L = 6 symmetry.