Nuclear magnetic resonance Zeeman effect

Thus, for 7 = J, the energy levels are represented in Fig. 3. This is the nuclear Zeeman effect and is the basis of nuclear magnetic resonance. 

If the g-factors (polarizabilities) are known in advance, it is possible to measure a static magnetic (electric) field by means of the Zeeman (Stark) effect. This is useful particularly in such situations as in hot plasma and in astronomical objects where the standard field-measuring probes, e.g. a nuclear magnetic resonance probe and a Hall probe, are unusable. 

We calculate the effects of the Hamiltonian (8.105) on these zeroth-order states using perturbation theory. This is exactly the same procedure as that which we used to construct the effective Hamiltonian in chapter 7. Our objective here is to formulate the terms in the effective Hamiltonian which describe the nuclear spin-rotation interaction and the susceptibility and chemical shift terms in the Zeeman Hamiltonian. We deal with them in much more detail at this point so that we can interpret the measurements on closed shell molecules by molecular beam magnetic resonance. The first-order corrections of the perturbation Hamiltonian are readily calculated to be... 

The rotational and Zeeman perturbation Hamiltonian (X) to the electronic eigenstates was given in equation (8.105). It did not, however, contain terms which describe the interaction effects arising from nuclear spin. These are of primary importance in molecular beam magnetic resonance studies, so we must now extend our treatment and, in particular, demonstrate the origin of the terms in the effective Hamiltonian already employed to analyse the spectra. Again the treatment will apply to any molecule, but we shall subsequently restrict attention to diatomic systems. 

Many other diatomic molecules with1X ground states have been studied by molecular beam magnetic resonance. Where magnetic nuclei are present, magnetic focusing is based upon the nuclear Zeeman effects. This is the case with 15N2 for which the... 

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