Energy transfer from paramagnetic ions to a lattice through rapidly relaxing centers

Spin-lattice relaxation is analyzed in a crystal containing two types of paramagnetic centers having approximately equal resonant frequencies but markedly different spin-phonon couplings. It is assumed that for the centers having the strong spin-phonon coupling this coupling is stronger than the spin-spin coupling with other paramagnetic centers. The Green's function method is used. The spin-lattice relaxation time for the centers coupled weakly with the lattice through rapidly relaxing centers is found as a function of the difference between the splittings of their spin levels, the strength of the spin-spin coupling between these centers, the concentrations of these centers, and the strength of the spin-phonon coupling over rapidly relaxing centers. © 1972 Consultants Bureau

The role of the non-secular spin-spin interactions in nuclear relaxation

The role of the connection between the secular part of the spin-spin interactions through the non-secular spin-spin interactions with the Zeeman paramagnetic reservoir in nuclear relaxation is considered. Conditions have been determined under which the Zeeman nuclear energy is transferred to the Zeeman impurity reservoir. © 1978

Dipole magic echo in thermodynamical systems

The irreversible evolution component of the subsystem of nonsecular dipole-dipole interactions under conditions of time inversion is considered on the basis of the nonequilibrium thermodynamics methods. The abridged description of the spin system evolution is effected with the help of projection operators and the introduction of the temperatures of secular, nonsecular and Zeeman subsystems. Consideration of cross-correlation attenuation during the emergence of the temperature in the sub-system leads to a good agreement with experiment