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

Abstract

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 <i>R</i>/<i>S</i>-methylbenzylammonium (<i>R</i>/<i>S</i>-MBA) into Cu-I inorganic skeletons to achieve chiral tetranuclear (<i>R</i>/<i>S</i>-MBA)₄Cu₄I₄ clusters with intense orange luminescence and CPL activity at room temperature. These enantiomeric (<i>R</i>/<i>S</i>-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 (<i>R</i>/<i>S</i>-MBA)₄Cu₄I₄ clusters and their largely distorted polynuclear configuration demonstrate a new platform for the study of chiral-related properties.