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Synthesis and Characterization of Amphiphilic Gold Nanoparticles
Published on: July 2, 2019
Amphiphilic paramagnetic neutral gold dithiolene complexes
Romain Perochon1, Lydia Piekara-Sady, Witold Jurga
1Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes I, Campus de Beaulieu, F-35042, Rennes, France.
Dalton Transactions (Cambridge, England : 2003)
|April 9, 2009
Summary
Researchers synthesized novel gold dithiolene complexes with varying alkyl chains. These neutral radical complexes exhibit near-infrared absorption and unique spin delocalization, forming layered structures with antiferromagnetic interactions.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Dithiolene complexes are known for their interesting electronic and magnetic properties.
- Gold complexes offer unique opportunities for developing novel functional materials.
Purpose of the Study:
- To directly synthesize neutral radical gold dithiolene complexes with varying alkyl chain lengths.
- To investigate the structural, electronic, and magnetic properties of these novel gold complexes.
Main Methods:
- Sulfidation of benzils using phosphorus pentasulfide (P(4)S(10)) in 1,3-dimethyl-2-imidazolidinone (DMI).
- Synthesis of gold dithiolene complexes with n-butyl, n-octyl, and n-dodecyl chains (Au-OC(4), Au-OC(8), Au-OC(12)).
- Characterization using UV-Vis-NIR spectroscopy, Electron Paramagnetic Resonance (EPR), X-ray crystallography, and magnetic susceptibility measurements.
Main Results:
- Successfully synthesized three neutral and soluble gold dithiolene complexes.
- Observed near-infrared absorption bands around 1.5 µm and EPR signals indicating significant spin delocalization.
- X-ray structures revealed layered arrangements of alkyl chains and stacked radical complexes with antiferromagnetic interactions and a singlet ground state.
Conclusions:
- The synthesized gold dithiolene complexes possess unique electronic and magnetic properties due to spin delocalization.
- The structural organization influences the magnetic behavior, leading to antiferromagnetic interactions.
- These complexes represent promising candidates for advanced materials applications.
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