White light emission in water through admixtures of donor-π-acceptor siblings: Experiment and simulation

Donor-acceptor π-conjugated molecules with triphenylamine donor and different acceptor (H, cyano, and pyridinium) units with a double bond spacer were synthesized. These compounds exhibit bathochromic shifts in absorption and emission with an increase in the acceptor strength. Solvatochromic measurements in water reveal emitting states characterized by a polar nature with three distinct emission spectral regions from blue to red. Interestingly, binary mixtures of the stilbenes in acetonitrile and water gave white light emission. MD simulations of the admixtures reveal that the emission data directly correlate to the structural arrangements of the molecules driven by intermolecular and solvent interactions with micelle-like structural arrangements for one set and uniform homogenous mixing for the other two sets. Such a tunable emission strategy using simple structural siblings could offer great potential towards designing novel emitting systems.