TIME RESOLVED ELECTRON-PARAMAGNETIC RESONANCE SPECTROSCOPY OF ANTHRACENE IN FROZEN AQUEOUS MICELLAR SOLUTIONS - TRIPLET YIELDS AND LIFETIMES

Anthracene in frozen aqueous micellar solutions of n-alkyltrimethylammonium halides, C//nTAX(n equals 10, 12, 14, 16, 18; X equals I, Br, Cl), was subjected to laser pulse excitation in the cavity of an EPR-spectrometer. Decaying triplet signals were recorded with a signal processing unit designed for time resolution in the ms-range. Measured triplet lifetimes tau //T at 80 K were lowest in C//1//6TAI-solutions, highest in C//nTACl-solutions, and varied with n; relative triplet quantum yields phi //T were lowest in C//1//6TAI and highest in C//nTACl-solutions. Relative fluorescence quantum yields phi //F were also higher in C//nTACl- than in C//nTABr-solutions.