We discuss first the case of Fe(bpac)Fe(CN)4. In LS, CO2 binds on top of the Fe site in a tilted top on configuration (see Fig. ) (similar to the molecular case discussed in the previous section) with the O atom of CO2 on the two apical sites of the octahedron at a bond distance of 2.314 Å. In HS (S=1), the bond distance increases substantially (3.379 Å), as expected, and the molecule orients parallel to the Fe(CN)4 plane and parallel to the plane of the pyridine rings and in between them. We note that this configuration differs from the molecular case where CO2 binds in a top on fashion (see Fig. and Tab. 1) and we attribute this difference to the important role of the pyridine rings of bpac when the affinity for the metal is low. In LS, N2 and CO adsorb on a top on configuration with the N-N and C-O bond perpendicular to the Fe(CN)4 plane (see Fig. b and a, respectively). At S=1, the N2 molecule maintains its orientation while increasing the bond distance. The configuration with CO in S=1 could not be converged (vide infra). H2 binds in an side on horizontal configuration (see Fig. ) as expected from a Kubas type of binding in LS (H-Fe bond distance of 1.656 Å). In S=1 the bond distances increase and the molecules are found in a slightly tilted configuration.