Molecular clusters

Clusters are ultrasmall particles with about 1 nm size composed of a dozen atoms and show peculiar catalytic, optical, and magnetic activities. In contrast to bulks and nanoparticles, adding or eliminating only a single atom drastically changes a cluster's properties due to its amorphous structure and quantum size effects. Interestingly, some clusters called superatoms have atom-mimic electronic configurations and characteristics; thus, the periodic table of clusters has been proposed. Recent developments allow us to obtain clusters in the gas, liquid, and solid phases and use them as materials. Clusters will be new building blocks in future science.