Tailoring the structure of 32-metal-atom nanoclusters by ligands and alloying

Abstract Alloy nanoclusters (NCs) are of particular interest because of the rich behavior of interactions between the metal components in the particle. Herein, we report the synthesis and atomic structure of a [Ag 20 Cu 12 (SR) 14 (Dppm) 6 Br 8 ] 2+ NC (SR = 2,4-dimethylbenzenethiol (SPhMe 2 ), Dppm = bis-(diphenylphosphino)methane). The atomic arrangement of Ag and Cu atoms in Ag 20 Cu 12 is determined by x-ray crystallography. This NC consists of a Ag 17 core, which is capped by a surface shell of Ag 3 Cu 12 (SR) 14 (Dppm) 6 Br 8 . The surface shell is formed by assembly of two Ag 1 Cu 6 (SR) 7 (Dppm) 3 Br 4 staples through a silver atom, and furthermore, the Ag 1 Cu 6 (SR) 7 (Dppm) 3 Br 4 staple is assembled from Cu 2 (SR) 3 (Dppm)Br and AgCu 3 (SR) 4 (Dppm) 2 Br 3 units linked by a copper atom. In this Ag–Cu alloy NC, the Cu atoms are selectively incorporated in the staples. Overall, this study demonstrates a strategy of tailoring the NC structure by engineering the ligands and alloying different metals.