Thulium, spin measurements

Today the lanthanide eontraction is still one of the most important tools available to the scientist in applying systematics to the behavior of lanthanide materials. Deviations from the lanthanide contraction established for a given compound series gives a measure of anomalous valences for cerium, samarium, europiun, thulium and ytterbium (see section 3.2) which are important in evaluating the nature of these elements in valence fluctuation, heavy fermion, and spin fluctuation behaviors (see section 4.4.4). 

The relaxation mechanism, connected with the random thermal excitation of the host lanthanide ions in VV paramagnets, proves to be effective for impurity ions too. We list the results of the relaxation rate measurements for a number of impurity lanthanide ions in TmES and LiTmF4 crystals (Aminov et al. 1986, 1989) (table 18). As for other investigations in this field, we may refer only to papers by Rimai and Bierig (1964), Rachford and Huang (1971), and Antipin et al. (1979) and only in the first of these papers was the influence of thuliiun ions on spin-lattice relaxation of Fe ions in thulium garnets observed with certainty. 

The thulium nuclear spin-lattice relaxation times Ti in TmBa2Cu30fr,.j were measured using TtH-n-t-nH-Ti pulse sequence and observing the recovery of the spin echo intensity Ax (Bakharev et al. 1993, 1994). It appeared that for all samples at r 4.2K, the recovery curve was fairly well described by Forster s law ... 

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