Dual fluorescence in trans-4-dimethylamino-4′-cyanostilbene revealed by picosecond time-resolved spectroscopy: A possible new “TICT” compound

Fate of photoexcited trans-aminostilbenes

“…The TICT-forming argument on trans-aminostilbenes was first proposed for trans-4-(N,N-dimethylamino)-4 0 -cyanostilbene (4DCS) [42][43][44][45], which could be considered as a p-extended DMABN by replacing the phenylene group with a stilbene group. Interestingly, the TICT state proposed for 4DCS is not from the torsion of the phenylene-amino C ph À ÀN bond but that of the vinylene-anilino C v À ÀC an bond.…”

Conjugated Oligomers with Terminal Donor–Acceptor Substitution

“…The aldehyde series 33 a, 34 a, and 35 a with the corresponding donor groups D acted as the central series and were constructed by means of the Wittig reaction with the extension reagent 36. [46, 58b, 59] Compounds analogous to 38 b-40 b, but with a CN group instead of the NO 2 group, were investigated in the context of their dual fluorescence and twisted intramolecular charge transfer (TICT) states; [60][61][62][63][64][65][66] however, a discussion of these states is beyond the scope of the present Review. [57] The maxima of the long-wavelength absorptions of a selection of compounds 33-35 are listed in Table 3.…”

Study of the intramolecular charge-transfer (ICT) process in 4-dimethylamino-4′- nitrostilbene by picosecond time-resolved CARS

“…Comparison with DCS derivatives where single bond twisting has been blocked indicated that the CRICT state formation should involve the rotation of the dimethylanilino group and a strong interaction with the polar solvent. 3,4,8 Although the photophysics of DCS has been clarified, information about the similar 4-dimethylamino-4 0nitrostilbene (DNS) molecule remains limited. Compared with DCS, a peculiar fluorescence behavior of DNS is observed: the fluorescence quantum yield increases from weakly polar to moderately polar solvents and then decreases in highly polar solvents.…”