Interaction between oxygen and aromatic molecules

Abstract

The quenching of electronically excited aromatic molecules is discussed, employing a “golden rule” formalism for the quenching. Attention is focussed on the electronic matrix elements for the charge-transfer and electron exchange mechanisms. Singlet quenching is shown to be diffusion controlled in solution and to yield preferentially higher excited triplet states. Relaxation to a charge-transfer state is shown to be unimportant. Triplet quenching is shown to yield almost exclusively ¹Δ_g excited oxygen. Induced absorption is considered and a comparison with experimental data is made. A short discussion of the effect of NO as a perturbing molecule is presented.