Singlet-triplet phosphorescence emission energies were calculated for the complexes for which dynamics simulations were performed. As a first step, for each complex, for each of the 100 trajectories, the latest-time geometry was taken where the complex was still in a singlet state and a geometry optimization was performed in the LVC model potentials using the SHARC program and the ORCA optimizer. For each of the complexes, ca. half of the 100 optimizations converged to singlet minima; in each case, the converged geometries were structurally very similar. For each complex, one of the LVC-optimized singlet geometries was then taken, and a geometry optimization at the DFT level of theory using the same parameters as in Section S1.1 was performed. At these DFT-optimized geometries, then CASSCF/CASPT2 calculations using the (13,10) active spaces from Section S1. In our previous study, we simulated the excited-state dynamics of VCl 3 (ddpd) using surface hopping on LVC potentials parametrized using CASSCF. Here, we performed the simulations of VCl 3 (ddpd) again while using the combined CASSCF/CASPT2 approach to parametrize the LVC potentials, see Section S1. ) Mechanisms describing the excited-state dynamics. Labels on top of the states denote populations at the start of the dynamics, while labels on top of the arrows denote the importance of the reaction pathway (see also Section S6). tials, the dynamics are started mainly in the 3 T 1 ′ states (94% initial population). From, there, the majority of the population (70%) relaxes via the 3 A 2 states to the 3 T 2 states.