In this study, we have used the (30,22) active space of Ref. 39, which was divided into two fragments centered on the Cr atoms. The active space had 3s, 3p, 3d and σ Cr-OH and σ * Cr-OH orbitals. Using SA-LASSCF and taking the AVAS initial guess we have optimized the orbitals for the sextet state (i.e. each fragment has S= 3 2 ). These orbitals with their occupancies are depicted in Table of the SI. Using these orbitals, we determined the spinstate spectrum employing LASSIS and LASSIS-PDFT, as well as DMRGCI and DMRGCI-PDFT for reference. All methods consistently predict a singlet ground state (see Table ).