AIE/ACQ effects are presented in Fig. . The emission intensities were normalized to 1 at the point where the AIE starts for dyes with R ′ =CF3. The presence of CF3 group attached to phenyl (dyes 3, 6 and 9), regardless of R, introduces AIE behavior with a lower THF/water ratio than for the H-or OMe-substituted phenyls (blue lines, Fig. ). The highest increase of emission intensity, compared to the dilute THF solution, was observed for compound 3 featuring DAA topology (blue, Fig. ). On the other hand, the most efficient quenching of emission occurs for compound 7, isomer of 3, representing AAD pattern (yellow, Fig. ). Although the introduction of hydrophobic (CF3) or slightly hydrophylic (OMe) substituents can be useful from biomedical point of view, the comparison of regioisomers 3 and 7 reveal that substituents' flip controls aggregation-assisted fluorescence change. Similarly, the opposite behavior is observed for 2 and 4, but not for 6 and 8, suggesting that for the effective switching between AIE and ACQ the donor group is essential, a structural feature not fulfilled for 6 and 8.