Relaxation Processes in NQR Multiple-Pulse Spin-Locking

Abstract

A theory of the spin-lattice and spin-spin relaxation processes in quadrupole spin systems with I > 1/2 in the situation of the multiple-pulse NQR spin locking is proposed for the pulse sequence MW-4. The theory is based on the assumption that for t >~T2the change of the spin system is a quasi-equilibrium process. Rate equations for inverse generalized temperatures are obtained and the kinetic coefficients calculated for the case of exponential correlation functions. The above assumption was confirmed for some substances containing the 35C1 and 123Sb, and the time constant T1e characterizing the spin echo signal decay was investigated and compared with the time constant T1Q in the case of continuous spin locking. © 1986, Verlag der Zeitschrift fur Naturforschung. All rights reserved.