The theory of both nuclear resonance energy absorption and the relaxation of a coherent magnetization transverse to an applied external magnetic field is developed for nuclei in a mechanically rotating solid. The consequences of the formalism in the simple case of a solid composed of effectively isolated nuclear pairs is presented. For the more general nuclear lattice, a procedure for isolating and experimentally measuring the "exchange" interaction between the nuclei in the solid is proposed. Finally, the moments of the energy absorption line shape for the rotating solid are investigated and the second and fourth moments are explicitly calculated.

• Received 13 February 1961

DOI:https://doi.org/10.1103/PhysRev.123.835