title: Composite Icosahedron/Cube Endohedral Clusters in Rh2Cd15.
abstract: We present Rh2Cd15, the first binary compound in the Rh-Cd system. It is based on transition-metal-embedded (Rh@Cd11 and Rh@Cd12) endohedral Cd clusters that are single- and double-capped IC10 composite icosahedra/cubes. We demonstrate the structural connections between the clusters. On the basis of the analysis of atomic interactions and electron counting, 50 electrons per Rh2Cd15 is postulated to be the boundary between bonding and antibonding interactions. This understanding is supported by electronic structure calculations showing that the electron count for Rh2Cd15 (48 electrons per Rh2Cd15) is located close to a deep pseudogap in the electronic density of states at 50 electrons per formula unit, which we postulate is an important factor in determining the new compound's stability.
authors.affiliation: Department of Chemistry, Princeton University , Princeton, New Jersey 08540, United States.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Xie
authors.affiliation: Department of Physics, Princeton University , Princeton, New Jersey 08540, United States.
authors.forename: Minhao
authors.initials: M
authors.lastname: Liu
authors.affiliation: Department of Physics, Princeton University , Princeton, New Jersey 08540, United States.
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Physics, Princeton University , Princeton, New Jersey 08540, United States.
authors.forename: Nai-Phuan
authors.initials: NP
authors.lastname: Ong
authors.affiliation: Department of Chemistry, Princeton University , Princeton, New Jersey 08540, United States.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Cava