A theoretical study of the ¹⁴N and ¹⁷O N.M.R. shifts in lanthanide complexes

Abstract

The experimental ¹⁴N and ¹⁷O n.m.r, results in a series of lanthanide complexes are successfully interpreted from a second-order perturbation treatment of the calculation of (S₂), where bonding effects and spin-orbit coupling mixing are incorporated. The isotropic hyperfine interaction constants are shown to be negative for ¹⁴N and positive for ¹⁷O but both independent of the particular lanthanide ion. We also confirm that the 4f orbitals are not involved in direct bonding with the ligands.