White-light emission from simple AIE–ESIPT-excimer tripled single molecular system

Abstract

A simple organic molecule (L₃) has been systematically designed and developed to generate white-light emission from a single-component system. It could also tune several emission colors owing to its diverse spectral nature with varying water fractions in methanol–water and acetonitrile–water mixtures. Essentially, the introduction of an aggregation-induced emission (AIE) phenomenon and excimer-forming ability in the molecular system provided the scope for a dual emission, whereas ESIPT (excited state intramolecular proton transfer) coupled-AIE phenomenon acted as an additional means of adjusting the emission wavelength of the corresponding emission peak by varying the solvent polarity. Detailed AFM (atomic force microscopy), DLS (dynamic light scattering) and X-ray crystallographic studies were carried out to validate the mechanism of generation of white-light emission.