To address the second point, we compare the calculated shifts from a range of DFT computational methods employing different functionals and basis sets. The effects of including extra polarization functions in the basis sets, Hartree-Fock (HF) exchange energy in the DFT functionals, and dynamical correlation energy correction for the CAS space have already been studied by Vaara et al. in the derivatives of the CoTp 2 complex . In this work we went further by comparing the effects of the DFT functionals across the DFT functional hierarchy combined with basis sets designed for accurate hyperfine calculations. To reduce computational error in the calculated magnetic anisotropy of the paramagnetic center from CAS methods, [M(AcPyOx) 3 (BPh)] + complexes of Mn 2+ and Ni 2+ ions that do not have significant first-order orbital contributions are discussed (experimental NMR shifts from the Ref. ). The zero-field splitting (ZFS) and g-shift from the freeelectron value (g e = 2.023) are small enough in these complexes to introduced significant electron-nuclear dipolar effects. So the paramagnetic NMR shifts and the observed broad paramagnetic linewidth in these two transition metal ion complexes are mainly due to the Fermi-contact interaction and are therefore used to study the efficiency of the DFT based methods in characterizing them.