Ligand-Protected Golden Fullerene Au42 with Unprecedented Metal Coordination Number of 15

Abstract

A golden fullerene with a composition of [Au42(Ph3P)10(5-CF3-Hpa)8] (CF3COO)2 (5-CF3-H2pa = 5-trifluoropyridyl-2-amine) ( Au42 ) has been synthesized with pyridylamino and phosphine ligands as the protecting agents. Single crystal X-ray structural analysis reveals that the cluster has a D3h Au4210+ core, which can be depicted as a centered core-shell structure Au@Au15@Au26. The 41 Au atoms of the Au15@Au26 core-shell can be derived from placing a gold atom in the center of each polygon of C78 (D3h). 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 Au42 results from both the superatomic characteristics of the Au42 kernel and the gold-ligand interactions.