Aggregation-induced emission enhancement in halochalcones

A family of push-pull fluorophores, consisting of a chalcone core decorated with electron-donating substituents and halogen atoms, was designed and synthesized. Luminescence studies were performed in solution, aggregate form and in the solid state. Although some compounds are only weakly fluorescent in solution, all are emissive in the solid state showing aggregation-induced emission enhancement. In the crystalline state, the halogen atoms are not involved in halogen bonds but their presence strongly influences the aggregation-induced emission properties of the fluorophores.