Key points are not available for this paper at this time.
Mechanistic insights into photodissociation dynamics of transition metal carbonyls, like Fe (CO) ₅, are fundamental for understanding active catalytic intermediates. Although extensively studied, the ultrafast structural dynamics of these systems remain elusive. Using ultrafast X-ray scattering, we uncover the ultrafast photochemistry of Fe (CO) ₅ in real space and time, observing synchronous oscillations in atomic pair distances, followed by a prompt rotating CO release preferentially in the axial direction. This behavior aligns with simulations, reflecting the interplay between the axial Fe-C distances' potential energy landscape and non-adiabatic transitions between metal-to-ligand charge-transfer states. Additionally, we characterize a secondary delayed CO release associated with a reduction of Fe-C steady state distances and structural dynamics of the formed Fe (CO) ₄. Our results quantify energy redistribution across vibration, rotation, and translation degrees of freedom, offering an ultrafast microscopic view of complex structural dynamics, enhancing our grasp on Fe (CO) ₅ photodissociation and advancing our understanding of transition metal catalytic systems.
Schori et al. (Thu,) studied this question.