Integrating homogeneous photocatalysts into soft matter scaffolds represents an attractive option for the production of solar fuels. However, analysis of the involved and catalytically active states in the catalytic cycle of the catalyst is challenging because of the photochemical background of the scaffold.
In this study, we present a method involving combined efforts in theory and experiment that might help to overcome this issue. We modeled the optical behavior of the well-known photocatalyst (R2bpy)2Ru(tpphz)PtI2 using TDDFT calculation provided by Gaussian 16 package[1,2]. For the gas phase model, the Pt-to-tpphz transition is remarkably shifted into the low-energy region[3]. This optical transition could be used as a marker to identify the localization of the photocatalyst within a less polar polymer environment, thus providing an excellent tool for in situ characterization[4].
Respective experimental efforts in solvating the photocatalyst will aim for solubility in low polarity solvents such as toluene, which model gaseous environment.

We gratefully acknowledge support from DFG, TRR 234 Catalight Projects C5 and B2. Computer time on the JUSTUS cluster at Ulm University provided by the bwHPC initiative and the bwHPC-C5 project funded by the Baden-Württemberg government (MWK) and the German Research Foundation (DFG) is gratefully acknowledged.

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