@ST06775@ of geometries adopted by a molecule after initial electronic excitation, combined with a specification of the @ET07026@ at each geometry, from radiation absorption to product formation. Theoretically, this usually involves the computation of the MERP connecting the Franck–Condon point, located on the potential-energy surface of the spectroscopic state, to the final photoproducts located on the ground-state potential ?energy surface. Experimentally, a @P04585@ path can be probed by detecting transient species or reaction intermediates.