A general improvement in the results is obtained when the ligands are described by a single wave function optimized on the whole set of atoms present in the environment. Here note that the electron density of the ligands has been optimized under the influence of the density of the free metal ion, described by FAIMP model to avoid an empty region of space at the metal position, which would lead to un-physical repulsive interactions between the electrons of the environment (see FAIMP2 and NOGF2 graphs). In this case, while the percentage errors affecting the crystal field levels calculated by FAIMP method are still large for all the ions, it is impressive how the NOGF2 strategy, where the wave function of the ligands is mixed together with the wave functions of the isolated metal within the product functions, show results in pretty good agreement with those obtained at CAHF/CASCI-SO level on the whole system. This can prove the importance of including an accurate description for the electron density of the ligands, but also it seems to indicate that the rigid interaction (i.e. no orbital relaxation) between the metal density optimized on the isolated ion, and a suitable density which accurately describes the atoms in the environment, already suffices for the modelling of the crystal field splittings in these systems. Moreover, it indicates the overlap between the functions describing the different fragments to play an import role.