J. Phys. Soc. Jpn. 75S (2006) pp. 77-81  |Previous Article| |Next Article|  |Table of Contents|
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Proc. of 5th Int. Symposium on ASR-WYP-2005 – Advances in the Physics and Chemistry of Actinide Compounds –

NMR Studies of Actinide Compounds: The NMR of Actinide Nuclei

Russell E. Walstedt¹, Yo Tokunaga¹, Harukazu Kato², Hironori Sakai¹, Tatsuya Fujimoto¹, Shinsaku Kambe¹ and Hiroshi Yasuoka¹

In a brief recap of recent work on actinide NMR studies at JAERI, we review the direct observation of ²³⁵U NMR which has been carried out for both UO₂ and USb₂, as well as the estimate of T₁(T) for ²³⁵U which has been obtained from indirect (i.e., T₂ of ¹⁰³Rh) NMR studies of the Pauli paramagnet URh₃. New data for 1/T₁ vs T for ¹⁷O in NpO₂ are presented and analyzed. A sizeable fraction of the observed relaxation rate is strongly field-dependent, an effect attributed to a cross-relaxation process from the 100%-abundant, I = 5/2 ²³⁷Np nuclear spins. Analysis of this relaxation component leads to quantitative estimates of T_1Np (≃40 ns) and of anomalously enhanced values of the ¹⁷O–²³⁷Np nuclear spin-spin coupling. These effects as well as future prospects for actinide NMR studies are discussed.

URL: http://jpsj.ipap.jp/link?JPSJS/75S/77/
DOI: 10.1143/JPSJS.75S.77

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