Bimetallic Coinage Metal Complexes of Tetradentate ortho Ter arylene Ligands

Journal Article · Mon Jan 05 00:00:00 EST 2026 · ChemRxiv

DOI:https://doi.org/10.26434/chemrxiv-2026-14399· OSTI ID:3012424

Shariaty, Darius Allen ^[1]; Nattikalungal, Thabassum ^[1]; Djurovich, Peter I. ^[1]; Bradforth, Stephen E. ^[1]; Thompson, Mark ^[1]

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1. University of Southern California

The synthesis, structural and photophysical properties of five bimetallic coinage metal complexes of three tetradentate charge-transfer (CT) ligands are presented. The ligand structures incorporate donor/acceptor moieties electronically decoupled by ortho connection to a bridging biphenylene group. The M M distances observed in the crystal structures of the bimetallic complexes are shorter than the sum of the Van der Waals radii of the metal ions, suggesting stabilizing interactions between the d10 metal centers. Additionally, short distances between the bridging biphenylene and metal atoms suggest arylene metal interactions. Bimetallic Cu, Ag, and Au complexes of the ligand incorporating a carbazole donor and pyridyl acceptor (N2R22-) show absorption and emission energies that trend with the ionization potential of each metal, indicating metal character in the excited state. These properties contrast with our previously reported mononuclear Zn complex of N2R22-The structural and photophysical properties of five bimetallic d10 coinage metal complexes were presented. The M M distances observed in the crystal structures of the bimetallic complexes are shorter than the sum of the metals’ Van der Waals radii, suggesting attractive interactions between the d10 metal centers. Additionally, short distances between the bridging biphenylene and metal atoms suggest arylene metal interactions. The absorption and emission spectra of the bimetallic complexes redshift based on the oxidation potential of the metal ion. This suggests involvement of metal based orbitals in the excited state transitions of the bimetallic complexes, which was corroborated by molecular modeling. High photoluminescent quantum yields were observed in solution and in rigid media (up to PL = 0.75), and the excited state lifetimes in solution were found to exceed several microseconds.

• Research Organization: University of Southern California
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division (CSGB)
• Grant/Contract Number: SC0016450
• OSTI ID: 3012424
• Journal Information: ChemRxiv, Journal Name: ChemRxiv
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English