Ag₆ Cu₈ (C=CAr)₁₄ (DPPB)₂ : A Rigid Ligand Co-Protected Bimetallic Silver(I)-Copper(I) Cluster with Room-Temperature...

Area of Science:

• Materials Science
• Inorganic Chemistry
• Nanotechnology

Background:

• Ligands are critical for constructing metal clusters with tailored properties.
• Silver-copper bimetallic clusters are promising for various applications.
• Rigid ligands offer unique steric and electronic influences on cluster structures.

Purpose of the Study:

• To synthesize and characterize a novel Ag-Cu bimetallic cluster using a rigid acetylene ligand.
• To investigate the impact of the rigid ligand on the cluster's structure, stability, and photophysical properties.
• To elucidate the electronic origins of the observed fluorescence through computational methods.

Main Methods:

• Single-crystal X-ray diffraction for structural determination.
• Electrospray ionization mass spectrometry (ESI-MS) for fragmentation analysis.
• Nuclear magnetic resonance (NMR), UV-vis absorption, and photoluminescence spectroscopy for solution property investigation.
• Density Functional Theory (DFT) calculations to analyze electronic structure and energy gaps.

Main Results:

• A bimetallic cluster, Ag₆Cu₈(C=CAr)₁₄(DPPB)₂, was successfully synthesized.
• The rigid ligand caused distortion in Ag₂Cu₂ motifs and influenced cluster assembly.
• The cluster exhibited room-temperature fluorescence and excellent thermal stability, unlike clusters with flexible ligands.
• DFT calculations showed the rigid ligand lowers energy levels and reduces the band gap, suppressing non-radiative decay.

Conclusions:

• Rigid ligands can significantly influence the structural and photophysical properties of metal clusters.
• The synthesized Ag₆Cu₈ cluster demonstrates potential for applications requiring luminescent and thermally stable materials.
• Ligand design is a key strategy for tuning the electronic and optical properties of bimetallic clusters.