Abstract The photophysical and kinetic constants are completely determined by photostationary and time-dependent fluorescence measurements. Deviations from the usual reaction scheme at higher concen-trations are caused by a quenching process of the excimer by the unexcited monomer. This diabatic process which is not observed with pyrene and naphthalene takes place in spite of the short excimer lifetime. A possible correlation between internal conversion and diabatic reactivity is discussed.
Adiabatic and diabatic process of sum frequency conversion