Investigation of exchange of energy between Zeeman and dipolar reservoirs in the rotating frame in solids

Exchange of energy between Zeeman and dipolar reservoirs in the rotating frame during spin-lock has important implications for the understanding of the Hartmann-Hahn cross polarisation process and is examined here with experiments on ammonium dihydrogen phosphate. It is observed that energy exchange between the two reservoirs takes place indicating that the relative magnitude of the dipolar coupling in relation to the applied r.f. field may have a role to play in determining the rate of exchange of energy between the two reservoirs. (author). 10 refs., 4 figs