Asymmetric and Symmetric Dipole−Dipole Interactions Drive Distinct Aggregation and Emission Behavior of Intramolecular Charge-Transfer Molecules

Abstract

Three intramolecular charge-transfer (ICT) compounds with dithiole−nitrofluorene strong push−pull diads have been synthesized and fabricated into well-formed and morphology-controllable supramolecular self-assemblies. Although the difference in chemical structures of the compounds is slight, they exhibit rather distinct self-assembly behaviors driven by asymmetric or symmetric dipole−dipole interactions. The morphologies of the microsized suprastructures can be easily tuned by changing main operation parameters and the morphologies are observed to transit from kinetically to thermodynamically stable supraarchitectures. UV−vis spectra of the compounds are aggregation-dependent and the trinitro-substituted analogue (1a) is observed to be AIE active. The red emitting behavior of the well-formed hierarchical structured supraarchitectures endows the material with potential applications in the fields of OLEDs, molecular probes, biolabels, and so on.