Quasi-local oscillations in a solid containing chemically active particles: Effects on direct spin-lattice relaxation
A lattice model is discussed, in which there are pairs of chemically active particles capable of association. It is shown that the equilibrium position of the unassociated particles corresponds to an interaction that may be represented by a spring with negative rigidity. The low-frequency quasi-local oscillations in such a system are discussed in relation to the spin-lattice relaxation rate (on the assumption that at least one of the particles is paramagnetic). It is found that these oscillations substantially reduce the relaxation time for one-phonon processes. In principle, an analogous situation may be responsible for the very short relaxation times of exchange pairs at low temperatures.
KeywordsRelaxation Time Relaxation Rate Lattice Model Equilibrium Position Active Particle
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- 1.I. V. Aleksandrov and V. P. Sakun, ZhETF, 52, 136, 1967.Google Scholar
- 2.Yu. Kagan and Ya. Iosilevskii, ZhETF, 42, 259, 1962.Google Scholar
- 3.A. Maradudin, E. Montroll, and J. Weiss, The Dynamic Theory of Lattices in the Harmonic Approximation [Russian translation], Mir, Moscow, 1965.Google Scholar
- 4.Y. Kurita, J. Chem. Phys., 41, 3926, 1964.Google Scholar
- 5.Ya. S. Lebedev, DAN SSSR, 171, 378, 1966.Google Scholar
- 6.I. V. Aleksandrov, TEKh [Theoretical and Experimental Chemistry], 2, 67, 1966.Google Scholar
- 7.M. Klein, Phys. Rev., 131, 1500, 1963.Google Scholar
- 8.M. Wagner, Phys. Rev., 133, A750, 1964.Google Scholar
- 9.M. Wagner and W. E. Bron, Phys. Rev., 139, 1A, A223, 1965.Google Scholar