LONGITUDINAL AND ROTATING-FRAME SPIN-LATTICE RELAXATION IN C-13-ENRICHED DIAMONDS

The present paper is devoted to the first spin-lattice relaxation proc esses investigations in a new material: C-13-enriched diamond. Two sam ples with different amounts of impurities have been studied: a high pu rity colorless diamond, and one of greenish color. The efficiency of t he impurity spin-lattice relaxation mechanism was demonstrated by comp arison of the spin-lattice relaxation times for two samples under stud y. Impurity concentration for the greenish sample was estimated to (1- 3) x 16(17) cm-3 using the model of the impurity relaxation accompanie d by the spin diffusion. A weak T1 orientation dependence was obtained for the greenish diamond. Experiment data for the spin-lattice relaxa tion in the rotating frame are also presented. It was shown that the m agnetization recovery in the rotating frame conditions is established with two relaxation times.