Metal–Ligand Interface in the Chemical Reactions of Ligand-Protected Noble Metal Clusters

We discuss the role of the metal–ligand (M–L) interfaces in the chemistry of ligand-protected, atomically precise noble metal clusters, a new and expanding family of nanosystems, in solution as well as in the gas phase. A few possible mechanisms by which the structure and dynamics of M–L interfaces could trigger intercluster exchange reactions are presented first. How interparticle chemistry can be a potential mechanism of Ostwald ripening, a well-known particle coarsening process, is also discussed. The reaction of Ag59(2,5-DCBT)32 (DCBT = dichlorobenzenethiol) with 2,4-DCBT leading to the formation of Ag44(2,4-DCBT)30 is presented, demonstrating the influence of the ligand structure in ligand-induced chemical transformations of clusters. We also discuss the structural isomerism of clusters such as Ag44(SR)30 (−SR = alkyl/aryl thiolate) in the gas phase wherein the occurrence of isomerism is attributed to the structural rearrangements in the M–L bonding network. Interfacial bonding between Au25(SR)18 clu...