Triplet–triplet extinction coefficients of anthracene and 9-bromoanthracene determined by a ground state depletion method

Abstract

Extinction coefficients of the T-T absorptions for solutions of anthracene in benzene and cyclohexane and for 9-bromoanthracene in cyclohexane have been determined by flash photolysis using the ground state depletion method of Hadley and Keller. The respective values of ε_max obtained are 53 000 ± 2 000, 85 700 ± 3 200 and 66 500 ± 3 250 dm³ mol^–1 cm^–1. The T-T absorption spectra in the region of overlap with the ground state absorptions are also evaluated.