Stimuli-Responsive Circularly Polarized Luminescence of Gold Clusters Based on Hydrogen-Bond Driven Intercluster Coupling.

Stimuli-responsive circularly polarized luminescence (CPL) metal clusters hold significant potential in high-security encryption and sensing applications, yet the exploration of hydrogen-bond-driven CPL-active metal clusters remains limited. Here, we report the synthesis of an enantiomeric pair of rhomboid Au4 clusters utilizing chiral R/S-4-hydroxymethyl-5-methyloxazole-2-thione (R/S-HMMT) ligands. Two enantiomeric pairs of self-assembled metal clusters R/S-Au4(HMMT)4-blue and R/S-Au4(HMMT)4-red were obtained, by constructing distinct intercluster hydrogen bonds through the use of different crystalline solvents.

Tightly bonded excitons in chiral metal clusters for luminescent brilliance.

Chiral metal clusters have promise for circularly polarized luminescent materials; however, the absence of a unified understanding of the emission mechanism causes challenges in designing high-efficiency lighting materials based on these clusters. These challenges primarily arise from their vast structural variability and intricate emissive states. In this study, we show the crucial roles of the exciton binding energy and electron‒phonon interactions in achieving high-efficiency phosphorescence.