Effect of micelles on dual fluorescence of 2-(4′-N,N-dimethylaminophenyl)pyrido[3,4-d]imidazole

2-(4'-N.N-dimethylaminophenyl)pyrido[3,4-d]imidazole (DMAPPI) exhibits dual emission in sodium dodecylsulphate (SDS), cetyltrimethylammonium bromide (CTAB) and triton X-100 (TX-100) micelles. Normal and twisted intramolecular charge transfer (TICT) emissions are blue-shifted by 15-18 and 5-10 nm, respectively. In both cases, the DMAPPI molecule is located at the same site of the micelles. The greater stabilization in the TICT state has been attributed to the hydrogen bonding at the electron acceptor group. The enhancement in TICT emission is nearly the same in all the micelles, whereas the enhancement in normal emission is different in different micelles. (C) 2000 Elsevier Science B.V. All rights reserved.