Structurally Precise Dichalcogenolate-Protected Copper and Silver Superatomic Nanoclusters and Their Alloys.

Area of Science:

• Superatom chemistry and cluster science.
• Coordination chemistry and inorganic synthesis.
• Nanomaterials and solid-state chemistry.

Background:

• Chalcogenolato silver and copper superatoms are at the forefront of research, complementing extensively studied gold clusters.
• Crystal structure analysis is crucial for understanding the structure-property relationships and fabrication mechanisms of sub-nanometer clusters.
• Atomically precise clusters offer unique insights into fundamental chemical and physical phenomena.

Purpose of the Study:

• To present contributions to the development of dichalcogenolato silver (Ag) and copper (Cu) cluster chemistry.
• To elucidate the precise molecular structures and fabrication methods of novel Ag and Cu superatoms.
• To explore the impact of central atom doping and ligand modification on cluster architecture and properties.

Main Methods:

• Single crystal X-ray diffraction for precise structural determination of metal clusters.
• Galvanic exchange reactions for synthesizing bimetallic clusters.
• Spectroscopic techniques (absorption, photoluminescence) to investigate electronic and optical properties.
• Ligand exchange experiments to study structural and property variations.

Main Results:

• Fabrication of a unique two-electron superatomic copper cluster [Cu13{S2CNR}6{C≡CR'}4]+ with a cuboctahedral core, distinct from typical icosahedral M13 cores.
• Synthesis of bimetallic clusters via galvanic exchange, showing enhanced quantum yield upon doping (e.g., [Au@Cu12{S2CNnBu2}6{C≡CPh}4]+).
• Discovery of novel eight-electron silver superatoms with dithiophosphate and diselenophosphate ligands, exhibiting non-hollow icosahedral cores ([Ag21{S2P(OiPr)2}12]+, [Ag20{S2P(OiPr)2}12]).
• Identification of the first chiral silver superatom ([Ag20{S2P(OiPr)2}12]), arising from the removal of a capping silver ion.
• Demonstration of heteroatom doping-induced size-structure transformations, exemplified by the formation of [Au3Ag18{Se2P(OiPr)2}12]+.

Conclusions:

• The study establishes new synthetic routes and structural motifs for Ag and Cu superatoms, expanding the landscape of cluster chemistry.
• Central atom doping and ligand choice significantly influence cluster structure, stability, and photophysical properties.
• The findings highlight the potential for designing novel superatomic materials with tailored properties and the possibility of diverse structural isomers.