Visualization of Total Synthesis from Au₁₁ to Au₁₃ Nanoclusters.

Area of Science:

• Materials Science
• Nanotechnology
• Inorganic Chemistry

Background:

• Chemically preparing reduced metal nanoclusters (NCs) is feasible, as shown by geometrically related gold nanoclusters (Au11 and Au13) with 8 valence electrons.
• However, understanding the dynamic transformation pathways for structural evolution in NCs remains a challenge, hindering precise atomic-level synthesis control.

Purpose of the Study:

• To develop a method for systematic construction and continuous visualization of gold nanocluster (Au NC) synthesis and evolution.
• To elucidate the nucleation mechanism of icosahedral Au NCs and the influence of ligand modifications on their properties.

Main Methods:

• Utilized a large conjugated quinoline thiol ligand with protonatable sites for systematic Au NC construction.
• Employed crystallographic methods to synthesize and characterize a metastable Au12 NC intermediate (Au@Au11).
• Achieved continuous visualization of the core-shell evolution process from Au11 to Au13 NCs.

Main Results:

• Successfully synthesized seven structurally related Au11-13 NCs.
• Identified and characterized a metastable corner-missing gold icosahedron Au12 NC (Au@Au11) as a key intermediate.
• Demonstrated continuous visualization of the synthesis and core-shell evolution from Au11 to Au13 NCs.

Conclusions:

• Ligand engineering enables precise control over geometric rearrangement, electronic structure, and functional performance of Au NCs.
• Stepwise reaction pathways in the Au11-13 NC series show that metal NC synthesis can achieve organic chemistry-level precision.
• Provided unprecedented insights into the nucleation mechanism of classical icosahedral Au NCs.