Monitoring excited state dynamics in cis-[Ru(bpy)2(py)2]2+ by ultrafast synchrotron techniques

Photoactive metal complexes are applied in a variety of fields, including solar energy conversion, catalysis and medicinal chemistry. Their effectiveness depends on the excited-state features that control the nature of photoreaction intermediates and photoproducts. For this reason, the structural determination of light-induced transient species is fundamental for a rational design of novel photoactive metal complexes. Among the available time-resolved methods, synchrotron-based techniques are emerging as successful tools in detecting ultrafast structural changes in molecules. The aim of this contribution is to review the results obtained by our group combining TR-XSS (Time-Resolved X-ray Solution Scattering) and TR-XAS (Time-Resolved X-ray Absorption Spectroscopy) to study the excited state dynamics in cis-[Ru(bpy)2(py)2]Cl2, a model compound for ligand releasing applications. Besides a comprehensive summary of our previous work, we report here new findings we obtained by analysis of 100 ps-resolution TR-XSS dataset. The potential of these techniques towards applications in catalysis are discussed in comparison to other time resolved spectroscopies.