Dual excimer emission of p-terphenyl induced by gamma-cyclodextrin in aqueous solutions

Steady-state and time-resolved fluorescence spectroscopy of p-terphenyl( p- T) in an aqueous solution of gamma-cyclodextrin (gamma-CD) has revealed the presence of three emitting species, namely the focally-excited p-terphenyl , a low-energy excimer emitting at lambda(max) = 408 nm and a higher-energy excimer at lambda(max) = 390 nm. In the presence of beta-cyclodextrin (bet a-CD), only the locally-excited state is observed. The identity and the kin etics of the emitting species are discussed. This Letter reports on the det ection of excimer fluorescence for p-terphenyl. (C) 1999 Elsevier Science B .V. All rights reserved.