Multicolor luminescence and low-temperature phosphorescence from cucurbituril supramolecular assemblies: tuning clusteroluminescence via macrocycle size and substituents

Abstract

While the clusteroluminescence (CTE) of cucurbiturils has been established, a systematic understanding of how their macrocyclic structure dictates the emission efficiency remains elusive. Herein, we explore how polymerization degree and substituents affect the clusteroluminescence (CTE) of cucurbiturils. All tested Q[5–8] and methyl-substituted Q[6] crystals exhibited excitation-dependent fluorescence and phosphorescence. Q[6] and Q[7] exhibited superior multicolor emission, while methyl substitution weakened this property. Structural and theoretical analyses revealed CTE's dependence on self-assembled unit number and packing density.