David E. Townsend

The fluorescence spectrum and lifetime of the anthracene/trans, trans-2,4-Hexadiene exciplex

Abstract A weak transient fluorescence (φf ≈ 0.0036 and τ ≈ 27 ns) has been detected by employing single photon counting methods from solutions of anthracene, 6.7 × 10−5 M, and trans, trans-2,4-hexadiene, 1.76 M. This emission is tentatively assigned to the anthracene/1,3-diene exciplex and appears to confirm the mechanism for 1,3-diene enhanced anthracene photodimerization previously proposed for this system.

A triplet state path for adduct formation between benz[a]anthracene and the penta-1,3-dienes

Irradiation of benzene solutions of benz[a]-anthracene in the presence of either cis- or trans-penta-1,3-diene gives distinct sets of four products involving addition of C(7) and C(12) of benz[a]anthracene triplets to the C(1)–C(2) bond of the dienes.