Crystallographic Visualization of the Missing Structural Evolution of Copper Nanoclusters

Area of Science:

• Materials Science
• Chemistry
• Nanotechnology

Background:

• Copper nanoclusters are of significant interest in materials science and chemistry.
• Precise control over their synthesis is limited by a lack of fundamental understanding of structural evolution.

Purpose of the Study:

• To provide atomic-level insights into the structural evolution of copper nanoclusters.
• To demonstrate precise control over nanocluster growth kinetics and targeted synthesis.

Main Methods:

• Isolation of six distinct copper nanoclusters (Cu12, Cu23-a, Cu23-b, Cu25-a, Cu25-b, Cu61) from a single synthetic system.
• Utilizing a disulfide-mediated protection strategy with controlled reaction temperature and time.
• Employing single-crystal X-ray diffraction to determine cluster structures.

Main Results:

• Identified hexameric Cu3S3 and octameric Cu4S4 rings as key modular building motifs.
• Demonstrated that these motifs encapsulate metal kernels, directing the structural evolution of copper-thiolate nanoclusters.
• Observed structural isomerization within the homologous series of copper nanoclusters.

Conclusions:

• The study provides the first experimental evidence from a homologous series of size-incremental copper-thiolate nanoclusters.
• Fundamental building motifs and surface coordination chemistry cooperatively direct the targeted synthesis of functional copper nanoclusters.
• This work advances the fundamental understanding required for precise control over copper nanocluster synthesis.