Ligand-Protected Golden Fullerene Au with Unprecedented Metal Coordination Number of 15.

A golden fullerene with a composition of [Au(PhP)(5-CF-Hpa)] (CFCOO) (5-CF-Hpa=5-trifluoropyridyl-2-amine) (Au) has been synthesized with pyridylamino and phosphine ligands as the protecting agents. Single crystal X-ray structural analysis reveals that the cluster has a D Au core, which can be depicted as a centered core-shell structure Au@Au@Au. The 41 Au atoms of the Au@Au core-shell can be derived from placing a gold atom in the center of each polygon of C (D). Surprisingly, the centered gold atom of this noble cluster has the highest coordination number in metal nanoclusters of 15. Quantum-chemical studies suggest that the excellent stability of Au results from both the superatomic characteristics of the Au kernel and the gold-ligand interactions.