Spectroscopic Properties of Organic Azo Compounds

Abstract

Abstract Azo compounds are characterized by a low‐energy 1 (n,π * ) electronic state, which gives rise to a weak band at long wavelengths in the absorption spectrum. Coupling of this state with other low‐lying molecular states is responsible for the high intensity of the “azo band” compared to other forbidden transitions, for its lack of vibrational structure, and for the inability of nearly all organic azo compounds to fluoresce.