Structural studies of uranyl ion complexes of metalloligands and zwitterions, ligand classes with some degree of overlap, constitute a major contribution to more recent developments in uranium chemistry. To some extent, they have been focussed on basic product characterization but more generally on gaining an understanding of how particular features of ligand structure may influence the complete crystal structure and thus the potential for any applications. Metalloligands provide an obvious means of generating heterometallic complexes but since it is not always necessary to preform a metalloligand prior to its interaction with uranyl ion, they can be identified by somewhat arbitrary excision of appropriate components from a very large number of complete crystal structures, so that only selected examples are considered here. Zwitterion (and oligozwitterion) complex structures are treated more comprehensively, two subclasses here being those where the positive site is aprotic and those where it is protic, differing in the weak interactions involved. Association of zwitterionic ligands with classical, anionic polycarboxylates and with cucurbiturils are recent developments covered extensively.

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铀酰化学中的双功能配体：金属配体和两性离子

金属配体和两性离子的铀酰离子配合物（具有一定程度重叠的配体类别）的结构研究对铀化学的最新发展做出了重大贡献。在某种程度上，他们专注于基本的产品表征，但更普遍的是了解配体结构的特定特征如何影响完整的晶体结构，从而影响任何应用的潜力。金属配体提供了一种生成异金属配合物的明显方法，但由于并不总是需要在与铀酰离子相互作用之前预先形成金属配体，因此可以通过从大量完整晶体结构中任意切除适当的组分来识别它们，因此这里仅考虑选定的示例。两性离子（和寡两性离子）复合物结构得到更全面的处理，这里的两个子类是正位点是非质子的和那些是质子的，不同之处在于所涉及的弱相互作用。两性离子配体与经典阴离子聚羧酸盐和葫芦脲的结合是最近广泛报道的进展。