Aniline dimers and trimers as model compounds for polyaniline: steric control of charge separation properties

The photophysical properties of several derivatives of 4-aminodiphenylamine (ADPA), model compounds of aniline dimers and trimers are investigated. Se veral compounds show dual fluorescence with a charge transfer (CT) componen t with a significantly reduced fluorescence rate constant which can be supp ressed by bridging and enhanced by sterically hindering substituents, in cl ose similarity to the compounds showing twisted intramolecular charge trans fer (TICT). The relation to polyaniline (PANI) conductivity is also discuss ed. (C) 2001 Elsevier Science B.V. All rights reserved.