For the non-planar system B, all three types of IS are found within 3 kcal/mol of each other, making multireference character plausible. LS1, HS1 and HS2 have relative energies of about 10-15 kcal/mol while LS2 and HS3 lie considerably higher in energy. We note that LS2 and HS3 could only be obtained by enforcing orbital occupations with a negative HOMO-LUMOgap, i.e. locally excited states, leading to the assumption that a concave structure destabilizes such ring open shell systems. This can in part be explained by "classical" high-and low spin states LS1 and HS1 being stabilized by non-planar structures. Furthermore, the bent structure might lead to lower overlap of the iron d-orbitals and the ring orbitals, making a distribution of spin density on the ring less favourable.