Ion Exchange Transformation of Magic-Sized Clusters

High Resolution Image Download MS PowerPoint Slide Ultrasmall semiconductor clusters are exciting materials because of their molecularly precise structures and their unique optical spectra. “Magic-sized” CdSe clusters are transformed into their Cu 2 Se counterparts by means of ion exchange. We leverage the molecularly precise structure and high sensitivity of these clusters to investigate the mechanism of cation exchange. We optically identify a metastable intermediate in the solid-state transformation. Isolation and characterization of this intermediate provide insight into the dynamic structural rearrangement of the cationic sublattice in the course of cation exchange and the role of ligand passivation. Such understanding of the dynamics of ion exchange at the solid–liquid interface could help engineer improved materials for solid-state electrolytes and energy storage devices.