Magnetic properties diamagnetic term

A particularity of non-relativistic theory is that the introduction of vector potentials gives rise to second-order magnetic operators as well. These diamagnetic terms contribute as expectation values to second-order properties and are... 

The values of A have been tabulated. In the cases of Eu " and Sm ", there are substantial magnetic contributions from excited states. Eu " with a ground state of Fo, which is diamagnetic, depends totally upon the Fi,2.3 excited states, which are thermally accessible, for its magnetic properties. From the equation it follows that for one complex of any individual lanthanide, the relative dipolar shifts of all the nuclei are determined by their geometric relationship in terms of d,

isostructural series of complexes of different lanthanides, the shifts of analogous nuclei are related only by the values of A, assuming the crystal field parameters are not appreciably different. 

G. A. Aucar, T. Saue, L. Visscher, H. J. A. Jensen. On the origin and contribution of the diamagnetic term in four-component relativistic calculations of magnetic properties. /. Chem. Phys., 110(13) (1999) 6208-6218. 

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