Nuclear Relaxation and Slow Diffusive Motions in CaF2 and NaF
نویسنده
چکیده
Magnetic resonance is a wrell known tool for the investigation of atomic and molecular motions in solids and a large amount of work has been done in the past on this subject by studies of Zeeman (Ty/J spin-lattice relaxation time and dipolar line widths {To). More recently, the power of the NMR method has been still considerably improved bv the mea surements on rotating frame1,2 Tls and dipolar (jTh)) relaxation rates which are particularly sensi tive to extremely slowT spin motions in solids. This last method, together with conventional 7\z and To measurements is applied in this paper for the detection of slowr vacancy diffusion in mono crystals of CaFo and NaF. Detailed information about typical quantities like the activation enthalpy for vacancy diffusion and the formation energy of defect pairs is obtained.
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