A recent work presented a study on the role of the electrostatic interactions in the prediction of crystal field levels in lanthanide complexes . In that paper, the authors analyzed the ligand field generated by both different atomic charges distributions, and a more rigorous approach based on the Fragment Ab Initio Model Potential (FAIMP) method . Besides the electrostatic interaction, the FAIMP approach allows to include (i) the exchange interaction between the electrons of the ligand and the metal, and (ii) the Pauli's repulsion contribution originating from the requirement of orthogonality between the metal and ligand molecular orbitals, which prevents over-delocalization of the electrons of one fragment in the core regions of the other. The authors' conclusions are that the electrostatic approach, even at the ab initio level via a FAIMP approach, does not suffice for an accurate description of the crystal field levels in Ln(III) complexes, hence that covalency effects must play an important role.