
A new molecular cluster of silver composed of 152 atoms, protected with molecular linkers called ligands, having a mass of 25 kDa was isolated. This is the smallest cluster at which spectroscopic properties suggest the emergence of metallicity. Clusters are aggregates of atoms and molecules whose properties are distinctly different from the two extremes - atomic/molecular regime and the bulk. Atomically precise clusters of noble metals with novel properties have been chased by several research groups. These clusters have been studied often by mass spectrometry as their mass spectral signatures are unique. The overall composition of the new cluster isolated is Ag152(SCH2CH2Ph)60 where SCH2CH2Ph is the ligand. Computed structure of the cluster is unique in the sense that it has a 60 atom core and 92 atom shell covered with thiolate ligands. The clusters form crystals in which organised cluster assemblies are seen. This was published recently in Nano Letters.
