NMR studies of actinide oxides - A review

作者：Walstedt Russell E^*; Tokunaga Yo; Kambe Shinsaku

来源：Comptes Rendus Physique, 2014, 15(7): 563-572.

DOI：10.1016/j.crhy.2014.06.007

• Actinide oxides
• Multipolar order
• Nuclear magnetic resonance

In this paper, we offer a brief review of the ground-state properties of the cubic oxides AnO(2), where , Np, Pu and Am, as revealed mainly by NMR studies of the O-17(2-) ligand. For PuO2, where the ground state is a nonmagnetic singlet eigenstate of the cubic crystal field, only the Pu-239 has been studied, in a recent breakthrough observation of this elusive isotope [1]. For UO2 and NpO2, the former has an exotic four-sublattice antiferromagnetic (AFM) ground state, while the latter has the first multipolar ground state to be identified among actinide compounds, namely a mixture of octupolar and rank 5 (triakontadipolar) order. On the other hand AmO2, even with the longest-lived isotope Am-243, becomes disordered so quickly from radiation self-damage that its ground state in a recent study was simply a spin glass, while the actual ground state of the cubic crystalline compound remains obscured by this experimental problem. The emphasis throughout is on how O-17 NMR studies complement other experimental data to confirm and verify the known exotic magnetic ground states of AnO(2) systems.

• 出版日期2014-9