TPPQ has previously been reported as an AIE-active moiety. Aware of this, we assessed whether 4DMAC-TPPQ and 4PXZ-TPPQ would also show AIE and thus explored their PL spectra in THF/H2O mixtures (Figure ). Firstly, we re-confirmed AIE behaviour of TPPQ in THF/H2O mixtures. The emission peaking at 456 and 476 nm of TPPQ in THF slightly red-shifts and increases in intensity by 1.8fold upon increasing the water fraction (fw) to 60% (Figures and). On further increasing the fw beyond 80%, the emission intensity then decreases and red-shifts further to 492 nm. We confirmed the formation of crystalline aggregates by powder XRD (Figure ). Comparison of the powder XRD patterns to those simulated from the SC XRD data indicates structural differences, particularly in the cases of TPPQ and 4DMAC-TPPQ, likely arising from the influence of solvent and its ordering on the structures. However, in the case of 4PXZ-TPPQ, which lacks ordered solvent in its structure, a stronger similarity is seen between calculated and determined PXRD patterns. In comparison to TPPQ, 4DMAC-TPPQ shows very weak emission at lPL of 568 nm, while 4PXZ-TPPQ does not show any emission in THF, which points to non-radiative decay being significant in THF. Upon increasing fw to 80%, the lPL of 4DMAC-TPPQ red-shifts to 656 nm and becomes as much as 20-fold more intense (Figures and). Upon increasing the fw from 80 to 95%, the emission intensity slightly decreases and further red-shifts to 690 nm.