The new DFT based ligand field (LF) model is proposed to calculate the g- and A-tensors of [Co(acacen)] that is known to be a difficult case. The results obtained are compared with the ZORA approach implemented in ADF as well as with the experimental values. The calculations are in good agreement with the experimental data and demonstrate the ability of the method to reproduce the large anisotropy typical for this type of complexes. The ligand field-density functional theory method is therefore not simply a method to calculate multiplet structure, ligand field splittings and UV-Vis transitions, but is also appropriate to compute magnetic properties. (C) 2004 Elsevier B.V. All rights reserved.