Due to the primary interaction of electronic spectroscopy probes with the electronic wavefunction of the molecule, their sensitivity to structural dynamics, specifically the ringopening motion and its conrotatory or disrotatory nature, is very limited . Studies of the reaction by Fuß and coworkers using time-resolved multiphoton ionization mass spectroscopy yield extremely rich dynamics . This method is in principle, to some degree, sensitive to structural dynamics. However, it is extremely difficult to unambiguously correlate the observations to structural dynamics in the molecule, since changes in the transient photoion yields can originate from several different types of effects. These include pump-induced population dynamics between neutral excited states and structural evolution inside a given electronic state, which both can affect the photoion yield. Such effects can be further modulated in the multiphoton ionization probe process through resonance enhancements from higher-lying excited states and fragmentation in the ionic manifold, which are difficult to model .