Nonsuperatomic [Au23(SC6H11)16]− Nanocluster Featuring Bipyramidal Au15 Kernel and Trimeric Au3(SR)4 Motif

We report the X-ray structure of a cyclohexanethiolate-capped [Au23(SR)16]− nanocluster (counterion: tetraoctylammonium, TOA+). The structure comprises a cuboctahedron-based bipyramidal Au15 kernel, which is protected by two staple-like trimeric Au3(SR)4 motifs, two monomeric Au­(SR)2 and four plain bridging SR ligands. Electronic structure analysis reveals nonsuperatomic feature of [Au23(SR)16]− and confirms the Au15 kernel and surface motifs. The Au15 kernel and trimeric staple motif are unprecedented and offer new insight in understanding the structure evolution of gold nanoclusters.