Multiexponential spin-lattice relaxation of 125Te in tellurium due to ultraslow atomic motion

Nonexponential Spin-lattice relaxation is shown to result under selective excitation due to ultraslow site exchange. The hopping rate of the nuclei can be obtained directly without any further assumption on the nuclear spin interactions and spin thermodynamics. In tellurium single crystals hopping rates of Te-125 less than 1/sec have been observed.