Tridimensional structures of paramagnetic proteins in solution

NOEs or NOESY cross peaks can be used to define distances between protons. It is well known that the three-bond scalar coupling constants 3Jjj between nuclei / and J obey a Karplus relationship of the type [39,40] 

which provides the scalar coupling constant due to the interaction between nuclei, is analogous to Eq. (2.29), used to describe the dihedral angle dependence of the contact coupling constant due to the interaction between nuclei and electrons. 

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