Disc-Like Silver Nanocluster Ag Built with Bicapped Hexagonal Prismatic Ag and Ino Decahedral Ag Units.

The reduction of alkynyl-silver and phosphine-silver precursors with a weak reducing reagent Ph SiH led to the formation of a novel silver nanocluster [Ag (PPh ) (C≡CR) ] (R=4-CH OC H ), which is the largest structurally characterized cluster of clusters. This disc-shaped cluster has a Ag kernel consisting of a bicapped hexagonal prismatic Ag unit wrapped by six Ino decahedra through edge-sharing. This is the first time that Ino decahedra are used as a building block to assemble a cluster of clusters. Moreover, the central silver atom has a coordination number of 14, which is the highest in metal nanoclusters. This work provides a diverse metal packing pattern in metal nanoclusters, which is helpful for understanding metal cluster assembling mechanisms.