Thiolato Protected Copper Sulfide Cluster with the Tentative Composition Cu₇₄S₁₅(2-PET)₄₅

Area of Science:

• Nanomaterials Science
• Coordination Chemistry
• Biomedical Engineering

Background:

• Ligand-protected copper nanoclusters (CuNCs) exhibit unique photoluminescent properties.
• Precise structural information is vital for CuNCs' biomedical applications (contrast agents, biosensors, cell probes).
• Limited single-crystal structures of CuNCs are currently reported.

Purpose of the Study:

• To report the phosphine-free synthesis and structure determination of 2-PET protected CuNCs.
• To elucidate the structural characteristics and electronic properties of the synthesized cluster.
• To provide foundational knowledge for advancing CuNCs in biomedical fields.

Main Methods:

• Single crystal X-ray diffraction for structure determination.
• Computational calculations (DFT+TB) for electronic structure and optical properties.
• Synthesis of phosphine-free 2-PET protected copper nanoclusters.

Main Results:

• A binary sulfide cluster, Cu74S15(2-PET)45, with a rod-like structure was synthesized and characterized.
• The cluster core features fifteen bridged-sulfur atoms, with 45 thiol ligands on the surface.
• Computational analysis predicted the HOMO-LUMO transition and reproduced the absorption spectrum.

Conclusions:

• The study successfully synthesized and structurally determined a novel phosphine-free CuNC.
• The findings offer critical structural and electronic insights into chalcogenide-bridged copper clusters.
• This work facilitates the development of CuNCs for advanced biomedical applications.