Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Inorg Chem. 2012 Aug 20;51(16):8942-7. doi: 10.1021/ic301025f. Epub 2012 Jul 30.
Extended X-ray absorption fine structure measurements have been conducted on solutions of Pu(IV) with varying concentrations of sulfate anion in aqueous solution. Data support the periodic progression to primarily bidentate sulfate coordination about An(IV) centers when moving heavier in the actinides. This observation is attributed to the increase in Lewis acidity of the tetravalent actinides across the series, a consequence of the filling of the 5f orbitals and the actinide contraction. Though the changes in the chemical formation energies of the An(IV) complexes between Th and Pu are small, it is these small energetic differences that are critical to understanding how to effect more efficient and effective chemical separations among isovalent metal ions.
已对水溶液中 Pu(IV)浓度不同的硫酸盐阴离子溶液进行了扩展 X 射线吸收精细结构测量。数据支持了在镎系元素中，当原子序数增大时，An(IV)中心的硫酸盐配位主要从单齿向双齿发展的周期性趋势。这一观察结果归因于四价锕系元素路易斯酸度的增加，这是 5f 轨道填充和锕系收缩的结果。尽管 Th 和 Pu 之间的 An(IV)配合物的化学形成能的变化很小，但正是这些微小的能量差异对于理解如何在等价金属离子之间实现更高效和有效的化学分离至关重要。
