Abstract
Infrared multiple photon absorption is known to be observed in some triatomic and most polyatomic molecules. When the number of absorbed photons is high enough the process leads to photodissociation and excess energy is released as vibrational, rotational and translational energy in the electronic ground state of the fragments. The contribution of these energies is determined by standard methods, that include laser induced fluorescence, LIF, and time-resolved Fourier transform spectroscopy, TR-FTS. Examples of selected determinations are shown.Once produced, identified and characterized, the kinetic behaviour of the transients with selected reactants can be studied. In particular, removal rate constants of substituted carbenes, in specific vibrational and electronic states, by atoms, olefins and simple molecules are mentioned.