Abstract: Fluorescence spectroscopic properties of p-N,N-dimethylaminobenzonitrile (DMABN) in various kinds of surfactant micellar solutions were investigated. The results showed that the characteristics of the palisade layers of different surfactant micelles affected the twisted intramolecular charge transfer (TICT) properties of DMABN. In the ionic micellar solution, the electric field of the charged head-groups in the palisade layer was found to be a main affecting factor that promoting the formation of TICT state. The larger of the counterion dissociation degree, the stronger of Ia/Ib in the micellar solution. In the nonionic micellar solution, the effect of hydrogen bonding became distinct due to a large amount of water wrapped in the shell of the poly(ethylene oxide) (PEO) chains. Besides, the terminal hydroxyl groups of the short PEO chains were also able to hydrogen-bond with DMABN. In the view of photo-physics of DMABN, the anionic micelles with large dissociation degree of the counterions were suitable to as DMABN dispersed carriers for their TICT properties, for example, SDS or SDSO.

Key words: DMABN, TICT probe, Photo-physical property, Micellar effect