Excited complex formation between heterocyclic compounds and aromatic hydrocarbons and amines

Abstract

Many aromatic hydrocarbons in their excited singletstates form fluorescent exciplexes with heterocyclic compounds, e.g. furans, thiophens, pyrroles, and indoles. Dipole moments and enthalpies of formation for some of the exciplexes have been determined. In those cases where fluorescent exciplex formation was not observed, quenching rate constants were measured. Rate constant for the quenching of the excited singlet states of 2,4,5-triphenyloxazole and 2,5-diphenyl-1,3,4-oxadiazole by some amines have been measured and in some of the systems, fluorescent exciplex formation observed.