FLUORESCENCE OF 9,10-DIMETHYLANTHRACENE IN SOLUTIONS CONTAINING DIISOPROPYLNAPHTHALINE AND IN SOLID CYCLODEXTRIN COMPLEXES

Fluorescence and excitation spectra and fluorescence lifetimes of 9,10 -dimethylanthracene (DMA) were measured in the solvents n-pentane, tol uene, cyclohexane, decalin, diisoproylnaphthaline (DIPN), liquid paraf fin, and aqueous cetytrimethylammonium chloride (CTAC). Different visc osities had little influence on the fluorescence properties. The addit ion of increasing amounts of DIPN to cyclohexane solutions caused a gr adual increase of the fluorescence lifetime from 15 to 20 ns, which wa s not observed in the micellar CTAC solutions. The formation of ground state clusters of DIPN and DMA in cyclohexane was concluded from the concentration dependence of the effects. In solid complexes of DMA and cyclodextrins (CD), lifetimes up to 30 ns were measured. Complexes wi th gamma-CD can be prepared in such a way that either monomer emission or excimer emission is predominantly observed.