Circularly Polarized Luminescence from Chiral Tetranuclear Copper(I) Iodide Clusters

Circularly polarized luminescent (CPL) materials are promising
in applications such as 3D displays and quantum communication. Hybrid
organic–inorganic copper­(I) iodides have been rapidly developed
due to their intense photoluminescence and structural diversity; nevertheless,
the reported Cu–I clusters rarely show CPL activities. In this
study, we introduced chiral organic molecules R/S-methylbenzylammonium (R/S-MBA) into Cu–I inorganic skeletons to achieve chiral tetranuclear
(R/S-MBA)4Cu4I4 clusters with intense orange luminescence and CPL activity
at room temperature. These enantiomeric (R/S-MBA)4Cu4I4 clusters show
oppositely signed circular dichroism (CD) signals, which agree well
with their simulated electronic CD spectra. The crystallization-induced
helical arrangement of (R/S-MBA)4Cu4I4 clusters and their largely distorted
polynuclear configuration demonstrate a new platform for the study
of chiral-related properties.