Effect of Alkyl- vs Alkoxy-Arene Substituents on the Deactivation Processes and Fluorescence Quantum Yields of Exciplexes.

ABSTRACT: Decay processes of exciplexes of cyanoanthracenes with alkylbenzene donors were compared to those with alkoxybenzenes. For the three decay processes of exciplexes, the radiative rate constant (k_f) of alkoxy derivatives is slightly lower than those of alkylbenzenes at the same average exciplex energy. However, the corresponding deactivation rate constants, intersystem crossing (k_isc) and nonradiative decay (k_nr), are considerably higher. Consequently, the fluorescence quantum yields of the alkoxybenzene exciplexes are one-half to one-fifth of the corresponding alkylbenzenes at comparable emission energies. This trend is solvent-independent. The results can be rationalized in terms of the differing electronic character of the donor radica

SUBMITTER: Dinnocenzo JP 

PROVIDER: S-EPMC11684015 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature