Supramolecular Solid-State Microlaser Constructed from Pillar[5]arene-Based Host–Guest Complex Microcrystals

Herein we report a novel host–guest
complex single crystal
material based on a pillar[5]­arene (P5) and a laser dye trans-4-[p-(dimethylamino)­styryl]-1-methylpyridinium
iodide (DASP). Single crystal structure characterization
shows that two P5 molecules act as a supramolecular nanocapsule
for one isolated DASP molecule. This spatial confinement
effectively restricts aggregation-caused quenching (ACQ) effects and
other nonradiative channels (e.g., twisted intramolecular charge transfer),
leading to high luminescent efficiency of the isolated DASP. Together with its regular shape and smooth surface, each 2P5⊃DASP microcrystal forms a Fabry-Pérot (F–P)
microcavity and produces a stable laser output with a high Q factor and a low threshold.