Surface modifications of eight-electron palladium silver superatomic alloys

Area of Science:

• Nanomaterials Science
• Inorganic Chemistry
• Computational Chemistry

Background:

• Thiolate-protected coinage metal nanoclusters are well-established, but their selenium counterparts are challenging to synthesize.
• Palladium-silver nanoalloys offer unique electronic and structural properties.

Purpose of the Study:

• To synthesize atomically defined palladium-silver nanoalloys protected by dithiophosphinate ligands.
• To explore the synthesis and structural characterization of selenolate-protected palladium-silver nanoclusters.
• To investigate the isomeric diversity and structural properties of these novel nanoclusters.

Main Methods:

• Ligand exchange reactions and co-reduction methods were employed for synthesis.
• Single-crystal X-ray diffraction was used to determine the solid-state structures.
• Density functional theory (DFT) calculations were performed to rationalize structural preferences.

Main Results:

• A series of dithiophosphinate-protected palladium-silver nanoalloys [PdAg20{S2PR2}12] were successfully synthesized.
• The ligand exchange reaction yielded selenolate-protected palladium-silver nanoclusters [PdAg20{Se2PR2}12].
• The study identified different metal frameworks and symmetries for the PdAg20 cores, including the first reported isomeric pair of selenolate-protected nanoclusters with T and C3 symmetries.

Conclusions:

• This work expands the family of atomically precise coinage metal nanoalloys to include challenging selenium-protected systems.
• The discovery of isomeric selenolate-protected nanoclusters provides new avenues for exploring structure-property relationships.
• DFT studies support the observed geometrical isomerism in the PdAg20 core structures.