Magnetic moment origin

Figure 25 Scheme of antiferromagnetic collinear configuration of the magnetic moments originating from the Mn(II) ions, which constitute the chiral 3-D network compound [104]. 

A second type of structural information can be deduced from the hyperfine splitting in EPR spectra. The origin of this splitting is closely related to the factors that cause spin-spin splitting in proton NMR spectra. Certain nuclei have a magnetic moment. Those which are of particular interest in organic chemistry include H, " N, F, and P. 

Here Iais the magnetic moment of nucleus A and Ra is the position (the nucleus is the natural Gauge origin). Adding this to the external vector potential in eq. (10.62) and expanding as in (10.63) gives... 

Likewise, the original proton polarization can be transferred to other magnetically active heteronuclei, notably to 13C, 15N, 19F, 29Si, 31P or appropriate isotopes of various transition metals. This is especially attractive because of the frequently low sensitivity of many heteronuclei, in particular of those with low magnetic moments [8]. 

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