Doping the Golden Cage Au16- with Si, Ge, and Sn

We report a joint experimental/theoretical study of a series of group IV atom-doped gold anion clusters MAu 16 - (M = Si, Ge, Sn). We find that their global minima possess exohedral structures, which are dominated by the strong M−Au local interactions reminiscent of the MAu 4 clusters. In particular, a dangling Au atom is observed in the low-lying isomers of SiAu 16 - which confirms the Au/H analogy reported earlier in Si−Au mixed clusters. The nature of the dopant−Au local interactions is a critical factor in determining whether an impurity atom can be used to dope the golden cages.