To quantify the influence of geometry, equilibrium geometries were also derived using the common B3LYP functional as well as MP2. In the case of Fe(II), Co(III), and Cr(III) DFT geometry optimizations were performed in the D 3 point group. MP2 geometry optimizations used the C 2 point group, however, all results converged into a D 3 geometry. For Ni(III) and Co(II), no symmetry was applied in the DFT geometry optimization step, as we expected a Jahn-Teller distortion. The MP2 computations were also performed using the C 2 point group, however, this time the results did not converge into a D 3 geometry, but instead correctly predicted a Jahn-Teller distorted structure. In the case of Ni(III) MP2, the first 27 occupied orbitals were also subject to the frozen core approximation to assist convergence.