Synthesis, structural characterization and transformation of an eight-electron superatomic alloy, [Au@Ag19{S2P(OPr)2}12]Electronic supplementary information (ESI) available: Experimental data of 1 and 2, 31P NMR spectra of 1 and 2, XPS (1), EDS spectra of 1 and 2 and TD-DFT spectra. See DOI: 10.1039/c8nr00172c

• Main Authors: Lin, Yan-Ru, Kishore, Pilli V. V. N, Liao, Jian-Hong, Kahlal, Samia, Liu, Yu-Chiao, Chiang, Ming-Hsi, Saillard, Jean-Yves, Liu, C. W
• Format: Article
• Language: English
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/c8nr00172c

Controlling the metal nanoclusters with atomic precision is highly difficult and further studies on their transformation reactions are even more challenging. Herein we report the controlled formation of a silver alloy nanocluster [AuAg 19 {S 2 P(O n Pr) 2 } 12 ] ( 1 ) from an Ag 20 template via a galvanic exchange route. X-ray structural analysis reveals that the alloy structure comprises of a gold-centered Ag 12 icosahedron, Au@Ag 12 , capped by seven silver atoms. Interestingly upon reacting with one equiv. of silver( i ) salt, ( 1 ) can transform into a higher nuclearity nanocluster, [Au@Ag 20 {S 2 P(O n Pr) 2 } 12 ] + ( 2 ). The conversion process is studied via ESI mass spectrometry and 31 P NMR spectroscopy. This kind of size-structural transformation at the single atom level is quite remarkable. Furthermore, the compositions of all the doped nanoclusters ( 1 , 2 ) were fully characterized with ESI-MS and EDS. The blue shift depicted in the UV-visible and emission spectra of the doped nanoclusters ( 1 , 2 ) compared with the precursor, Ag 20 , demonstrates that the doping atoms have significant effects on the electronic structures. A superatomic alloy nanocluster (NC) [Au@Ag 19 (dtp) 12 ] from [Ag 20 (dtp) 12 ] has been synthesized and structurally characterized and its surface reconstruction to Au@Ag 20 has been demonstrated.