  We present a simple derivation of the nuclear shielding in paramagnetic
molecules, extendable to strong spin-orbit coupling cases of relevance to
lanthanides and actinides, as well as encompassing contributions from excited
multiplets. While our general formulation does not need electron paramagnetic
resonance parameters, using them a simple and practical expression is obtained
for the special case of the zero-field-split ground-state manifold, including
magnetic (Zeeman and hyperfine) couplings between the sublevels. The latter
method is implemented computationally and applied in the context of
first-principles calculations on example Ni(II) and Co(II) complexes.
