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Among gold species, gold thiolate compounds are an important class of materials due to the high affinity of gold atoms for sulfur-based molecules that can generate molecular complexes, oligomers, polymers, functionalized gold nanoparticles or self-assembled monolayers. Thus, in material chemistry, medicine and nanoscience, gold thiolate hybrid materials exhibit a very large domain of applications such as electronic devices, drugs, contrast agents, sensors, luminescent materials or catalysts. Among hybrid gold species, [Au(SR)]n gold-thiolate oligomers and polymers are a key step in the Brust-Schiffrin synthesis of functionalized gold nanoparticles and the formation of gold thiolate clusters. However relatively little is known about their structures, due to their high reactivity and insolubility, and their photophysical properties, except that it is correlated to the presence of aurophilic interactions.[1] Here we developed syntheses, in-depth structural characterizations and photophysical studies of new [Au(SR)]n gold-thiolate polymers. We discovered a rich variety of structures and luminescent behaviors depending on the thiolate ligands and the self-assembly.[2] In addition, when a reductor is added to these gold thiolate polymer solution, atomically well-defined gold thiolate clusters (denoted as [Aun(SR)m]) can be isolated.[3] Thus these monodisperse functionalized clusters, with gold core between 1 and 2 nm, hold promises as a new generation of perfectly defined catalysts. So to understand the subtle correlation of the structure of gold nanoparticles and their catalytic activity, we developed a new amino-functionalized gold cluster, [Au25(SPhNH2)18], and used it as a catalyst for aerobic oxidation reactions.[4]
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