Fig. 2. (a) UV/vis absorption of 4a, 6a and 8a in THF; c = 25 μg mL⁻¹. (b) PL spectra of 4a in THF/water mixtures with different water fractions (f_w); c = 0.1 mM; λ_ex = 342 nm. (c) Aggregation-induced polarization (AIP) of 8a in THF/water cosolvent; c = 2 mg mL⁻¹.