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Gold Clusters With Open-Shell Ligands: Superatom Mediated Magnetic Interaction
Katsuya Mutoh1, Kosei Hayashi1, Yoichi Kobayashi2
1Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, Osaka, Japan.
Angewandte Chemie (International Ed. in English)
|August 12, 2026
Summary
Researchers synthesized Ir-doped gold clusters functionalized with organic radicals. They observed electronic interactions and magnetic communication, paving the way for new magnetic nanomaterials.
Area of Science:
- Nanomaterials Science
- Supramolecular Chemistry
- Magnetism
Background:
- Superatomic orbitals in gold clusters are key for nanoscale magnetic materials.
- Functionalizing metal clusters with organic radicals offers new avenues for magnetic properties.
Purpose of the Study:
- To synthesize and characterize Ir-doped Au12 clusters with verdazyl radicals.
- To investigate the electronic, magnetic, and photophysical properties of these hybrid materials.
Main Methods:
- Synthesis of Ir-doped Au12 clusters functionalized with verdazyl radicals.
- Ultrafast time-resolved absorption spectroscopy.
- Electron Paramagnetic Resonance (EPR) spectroscopy at variable temperatures.
Main Results:
- Photoluminescence quenching upon radical functionalization.
- Evidence of electron transfer from the Ir@Au12 core to verdazyl ligands.
- Spin density delocalization and weak magnetic communication between radicals mediated by the cluster core.
Conclusions:
- Demonstrated electronic interaction between organic radicals and the Ir@Au12 superatomic core.
- Established superatom-organic radical hybrids as a new class of multi-spin systems.
- Provided a design strategy for photofunctional and magnetic nanomaterials.
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