We also note the high binding energy computed for CO2 in the case of Fe(III). It reaches a value of 1.599 eV in LS and 1.344 eV for IS, while for Fe(II) the computed values are substantially smaller (0.960 eV and 0.487 eV, for LS and IS), which is consistent with bond lengths values being significantly shorter for Fe(III): the metal-CO2 bond length is 2.06 and 2.42 Å for LS and IS for Fe(II), and 1.98 and 2.14 Å for Fe(III).