Surface chemistry of cadmium sulfide magic-sized clusters: a window into ligand-nanoparticle interactions.

Optoelectronic properties of nanoparticles are intimately coupled to the complex physiochemical interplay between the inorganic core and the organic ligand shell. Magic-sized clusters, which are predominately surface atoms, provide a promising avenue to clarify these critical surface interactions. Whereas these interactions impact the surface of both nanoparticles and magic-sized clusters, we show here that only clusters manifest a shift in the excitonic peak by up to 0.4 eV upon solvent or ligand treatment. These results highlight the utility of the clusters as a probe of ligand-surface interactions.