DFT Calculated xyz in Support of "Computational Modelling and Mechanistic Insight into Light-driven CO Dissociation of square-planar Rh(I) Complexes"

The C-H activation of alkanes mediated by electron-rich metal complexes, such as Rh(I) complexes, has drawn considerable attention in recent decades. In order to interact with the C-H bond, most Rh complexes, such as trans-Rh(PMe3)2(CO)(Cl) need to be activated through irradiation, which leads to the photocleavage of the Rh-CO bond and the formation of the active species Rh(PMe3)2(Cl). To elucidate the details of the photochemistry of trans-Rh(PMe3)2(CO)(Cl), we here present a computationally derived picture as obtained at the density functional level of theory (DFT) in combination with multireference wavefunction-based methods. We have identified that the photocleavage of CO proceeds via the metal-centered excited state, which is populated through intersystem crossing (ISC) from the dipole-allowed excited state S1. Moreover, the present study unraveled the reasons for the low C-H activation efficiency when using Rh featuring the bidentate ligand 1,2-bis(dimethylphosphino)ethane (dmpe), namely due to its unfavorable photochemical properties, i.e., the small driving force for light-induced CO loss and the fast deactivation of 3MC state back to the singlet ground state. In this study, we provide theoretical insight into mechanistic details underlying the light-induced CO dissociation process, for Rh complexes featuring PMe3 and dmpe ligands.