Spinning Sidebands and Recoupling Techniques

When the spinning speed is much less than the magnitude of the CSA, spinning sidebands are generated at multiples of the spinning rate, reminiscent of the spinning sidebands for liquid samples discussed in Section 3.3. The envelope of the sidebands approximates the shape of the CSA-broadened line in the absence of spinning, and analysis of the intensity pattern provides the values of cru (X2, and cr3. 

A number of recoupling techniques are utilized for specific purposes, but they all rely on synchronizing measurements, and, in most instances, pulse sequences, with the rotation period. For homonuclear recoupling (e.g., 13C-13C or 31P-31P), rotational resonance (R2) is based on magnetization exchange when the spinning rate wr is adjusted so that a multiple of it equals the chemical shift difference between the two dipolar coupled nuclei, and DRAMA (dipolar recovery at the 

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