Fullerene-Functionalized Monolayer-Protected Silver Clusters: [Ag29(BDT)12(C60)n]3- (n=1-9)

We report the formation of supramolecular adducts between monolayer-protected noble metal nano-clusters and fullerenes, specifically focusing on a well-known silver cluster, [Ag-29(BDT)(12)](3-), where BDT is 1,3-benzenedithiol. We demonstrate that C-60 molecules link with the cluster at specific locations and protect the fragile cluster core, enhancing the stability of the cluster. A combination of studies including UV-vis, high-resolution electrospray ionization mass spectrometry, collision-induced dissociation, and nuclear magnetic resonance spectroscopy revealed structural details of the fullerene-functionalized clusters, [Ag-29(BDT)(12)(C-60)(n)](3-) (n = 1-9). Density functional theory (DFT) calculations and molecular docking simulations affirm compatibility between the cluster and C-60, resulting in its attachment at specific positions on the surface of the cluster, stabilized mainly by pi-pi and van der Waals interactions. The structures have also been confirmed from ion mobility mass spectrometry by comparing the experimental collision cross sections (CCSs) with the theoretical CCSs of the DFT-optimized structures. The gradual evolution of the structures with an increase in the number of fullerene attachments to the duster has been investigated. Whereas, the structure for n = 4 is tetrahedral, that of n = 8 is a distorted cube with a cluster at the center and fullerenes at the vertices. Another fullerene, C-70, also exhibited similar behavior. Modified clusters are expected to show interesting properties.