See Figure 1 and 10 in the reference.
Palmer, A.G. & Massi, F. (2006). Characterization of the dynamics of biomacromolecules using rotating-frame spin relaxation NMR spectroscopy. Chem. Rev. 106, 1700-1719 [http://dx.doi.org/10.1021/cr04042875 DOI]
[[File:Fig1 Palmer Massi 2006.png|thumb|Try to reproduce Figure 1.]]
=== spin lock field ===