First-principles investigation of Au-covered carbon fullerenes

We investigate, by means of first-principles calculations, the possible formation of Au-covered carbon fullerenes. Coverages between 32 and 92 Au atoms over C-60 were considered. Among those, the most stable structure is Au92C60, which retains the I-h symmetry of C-60 after geometry optimization. Au92C60 has a small formation energy per Au atom (0.65 eV), which is in fact smaller than those of the Au-38 and Au-55 gold clusters, which were already observed. Au92C60 can be further stabilized by an overlayer of methylthiol molecules, which reduces the formation energy per gold atom to a value smaller than that of the bulk phase of gold.