Nonsuperatomic [Au23(SC6H11)16]- nanocluster featuring bipyramidal Au15 kernel and trimeric Au3(SR)4 motif

J Am Chem Soc. 2013 Dec 11;135(49):18264-7. doi: 10.1021/ja409177s. Epub 2013 Nov 25.

Abstract

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.