11 Fluorescent Chemosensors
401
Fig. 11.20 Molecular structures of AIE-active fluorescent chemosensors 10 and 11, and a schematic
illustration of their fluorescence turn-on behavior in the presence of analyte. Image adapted with
permission from Liu et al. (2008). Copyright 2008, American Chemical Society
Fig. 11.21 a Schematic illustration of photo-induced intramolecular charge transfer. Arrows denote
dipole moment of the dye. b A typical push–pull dye and its solvatochromism. Image adapted with
permission from Niko et al. (2013). Copyright 2013, WILEY–VCH Verlag GmbH & Co
In general, organic dyes exhibit larger dipole moments in the excited state than
in the ground state, except for ionic dyes like Reichart’s dye (Reichardt 2005). Such
a difference in dipole moment is especially pronounced for the push–pull dyes due
to their ICT characteristic. Therefore, their excited state is largely stabilized by the
surrounding solvent through dipole–dipole interaction along with conformational
401
Fig. 11.20 Molecular structures of AIE-active fluorescent chemosensors 10 and 11, and a schematic
illustration of their fluorescence turn-on behavior in the presence of analyte. Image adapted with
permission from Liu et al. (2008). Copyright 2008, American Chemical Society
Fig. 11.21 a Schematic illustration of photo-induced intramolecular charge transfer. Arrows denote
dipole moment of the dye. b A typical push–pull dye and its solvatochromism. Image adapted with
permission from Niko et al. (2013). Copyright 2013, WILEY–VCH Verlag GmbH & Co
In general, organic dyes exhibit larger dipole moments in the excited state than
in the ground state, except for ionic dyes like Reichart’s dye (Reichardt 2005). Such
a difference in dipole moment is especially pronounced for the push–pull dyes due
to their ICT characteristic. Therefore, their excited state is largely stabilized by the
surrounding solvent through dipole–dipole interaction along with conformational