IR spectroscopy applied subsequent to a proton transfer reaction in the excited state of isolated 3-hydroxyflavone and 2-(2-naphthyl)-3-hydroxychromone

IR/R2PI-spectroscopy has been applied to the electronic ground and electronically excited states of 3-hydroxyflavone (3-HF) and 2-(2-naphthyl)-3-hydroxychromone (2-NHC) in a supersonic jet yielding direct structural information on the educt and product of a proton transfer reaction. We show that IR spectra of the electronically excited states can be recorded subsequent to a photoinduced chemical reaction, in this case a proton transfer. In combination with DFT and TDDFT calculations structural assignments are performed.