The pivotal alkyne group in the mutual size-conversion of Au9 with Au10 nanoclusters
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Updated: Oct 29, 2025
A Simple Method for the Size Controlled Synthesis of Stable Oligomeric Clusters of Gold Nanoparticles under Ambient Conditions
Published on: February 5, 2016
Xiaohang Wu1, Ying Lv1, Yuyuan Bai1
1Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601 P. R. China. yuhaizhu@ahu.edu.cn.
Abstract:
Herein, density functional theory (DFT) calculations were performed to elucidate the mechanism of the reversible single atom size conversion between [Au10(DMPP)4(C6H11C[triple bond, length as m-dash]C)]3+ and [Au9(DMPP)4]3+ (DMPP is 2,2'-bis-(dimethylphosphino)-1,1'-biphenyl, the simplified, theoretical model of the experimentally used 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl). The presence of a unique alkyne group is pivotal to the nucleophilic attack of the phosphine ligand on the electron-deficient Au10 core. After that, a formal ligand exchange and facile 1,2-P (of the diphosphine ligand) transfer occur to generate the Au9 cluster product. By contrast, the absence of the alkyne group results in a relatively electron-rich Au9 core, and thus an electrophilic attack of the Au(alkyne) complex on the most electron-rich metal sites occurs first. After that, the Au(alkyne) migration on the cluster surface, 1,2-P transfer and core-reconstruction occur successively to generate the thermodynamically highly stable Au10 cluster product.
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