Use of holography to investigate photochemical reactions from higher excited states. Action spectrum of the second-photon step in the two-photon dissociation reaction of carbazole

A holographic technique has been used to investigate photochemistry that occurs from higher excited triplet states (i.e., T2 and above). Specifically, the two-photon dissociation of carbazole in poly(methyl methacrylate) films has been investigated. The photochemical action spectrum of the second-photon step is found to be in good agreement with the carbazole triplet-triplet absorption spectrum. This implies that the quantum yield for photodissociation is independent of photon energy in this wavelength region. © 1983 American Chemical Society.