The temperature dependencies of lanthanide-induced NMR shifts: Evaluation of theoretical approaches and experimental evidence

TL;DR: In this paper, the dependence of the room-temperature magnetic anisotropy Δχ of lanthanide complexes on the type of the coordination polyhedron and on the nature of the ion is quantitatively analyzed in terms of a model approach based on numerical calculations.

TL;DR: In this article, a comprehensive survey of the systems with three-and fourfold symmetry, for which these techniques have been applied, is proposed together with a detailed discussion of the limitations of Bleaney's approach for the modelling of paramagnetic anisotropies and the detection of structural changes along the lanthanide series.

TL;DR: The pseudocontact shift of lanthanide shift reagents as a power series of T − n, the reciprocal of temperature, developed by Bleaney has been extended to the T − 3 term as discussed by the authors.

TL;DR: In this article, the magnetic susceptibility of eight-coordinate lanthanide ions was modelled numerically for polyhedra resulting from distortions of the regular cube to a tetragonal prism, antiprism, and dodecahedron.

TL;DR: In this paper, the Fermi contact and pseudocontact contribution to isotropic NMR shifts in paramagnetic complexes are considered for the following cases, for which formulae customarily used are not strictly applicable: (1) there is an appreciable contribution to the magnetic moment of the complex from unquenched orbital angular momentum; (2) orbital contribution (induced by spin-orbit effects) from spin density at the ligand nucleus; (3) there are appreciable mixing of the ground electronic state and thermally populated excited states by the applied magnetic field