where F and K are the Fock and exchange matrices and λ is a tuning parameter used to generate different orbital sets. Increased λ values empirically correspond to candidate orbitals with more diffuse character. By generating different sets of orbitals with λ and choosing different numbers of virtual orbitals by varying N in the APC selection, a wide range of trial active spaces can be produced. DVS then selects between the trial wave functions generated from these active spaces by minimizing the tPBE energy averaged across the states of interest (e.g. the ground state and the target excited state). For small main-group molecule vertical excitations, this approach has successfully chosen good active spaces for a diverse set of excitations generated from DMRGCI wave functions. Here, we apply DVS exclusively to generated CASSCF wave functions for transition metal dimers.