Real-space observation of the dissociation of a transition metal complex and its concurrent energy redistribution

Abstract

The study focuses on the photodissociation dynamics of transition metal carbonyls, specifically iron pentacarbonyl (Fe(CO)₅), which is crucial for understanding active catalytic intermediates. Using ultrafast X-ray scattering, the researchers were able to observe the photochemistry of Fe(CO)₅ in real space and time. Key findings from the research include: Observation of synchronous oscillations in the distances of atomic pairs. A prompt release of a rotating carbon monoxide (CO) molecule, preferentially in the axial direction. This behavior is consistent with simulations and reflects the interplay between the potential energy landscape of the axial Fe-C distances and non-adiabatic transitions. A secondary, delayed CO release was also characterized, which is associated with a reduction of the steady-state distances of the Fe-C bonds and the structural dynamics of the resulting Fe(CO)₄. The results quantify the redistribution of energy across vibrational, rotational, and translational degrees of freedom. The study provides a microscopic view of complex structural dynamics, which enhances the understanding of Fe(CO)₅ photodissociation and contributes to the broader knowledge of transition metal catalytic systems.

Thomas Wolf

Staff Scientist

My research is focused on discovering structure-function relationships in ultrafast photochemistry to better understand and eventually control this type of reactions.