Peterson Appie, Kelly Sheridon N, Arino Trevor, Gunther S Olivia, Ouellette Erik T, Wacker Jennifer N, Woods Joshua J, Teat Simon J, Lukens Wayne W, Arnold John, Abergel Rebecca J, Minasian Stefan G
Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States.
Inorg Chem. 2024 Sep 30;63(39):18417-18428. doi: 10.1021/acs.inorgchem.4c02099. Epub 2024 Sep 16.
Amidate-based ligands (-(-butyl)isobutyramide, ) bind κ to form homoleptic, 8-coordinate complexes with tetravalent Np (Np(ITA), ) and Pu (Pu(ITA), ). These compounds complete an isostructural series from Th, U-Pu and allow for the direct comparison between many of the early actinides with stable tetravalent oxidation states by nuclear magnetic resonance (NMR) spectroscopy and single crystal X-ray diffraction (SCXRD). The molecular precursors are subjected to controlled thermolysis under mild conditions with the exclusion of exogenous air and moisture, facilitating the removal of the volatile organic ligands and ligand byproducts. The preformed metal-oxygen bond in the precursor, as well as the metal oxidation state, are maintained through the decomposition, forming fully stoichiometric, oxidation-state pure NpO and PuO. Powder X-ray diffraction (PXRD), scanning transmission electron microscopy (STEM), and energy dispersive X-ray spectroscopy (EDS) elemental mapping supported the evaluation of these high-purity materials. This chemistry is applicable to a wide range of metals, including actinides, with accessible tetravalent oxidation states, and provides a consistent route to analytical standards of importance to the field of nuclear nonproliferation, forensics, and fundamental studies.
基于酰胺的配体（-（-丁基）异丁酰胺）与κ结合，与四价镎（Np(ITA)）和钚（Pu(ITA)）形成同配、八配位的配合物。这些化合物构成了从钍、铀到钚的同构系列，并且通过核磁共振（NMR）光谱和单晶X射线衍射（SCXRD），可以直接比较许多具有稳定四价氧化态的早期锕系元素。分子前体在温和条件下进行可控热解，同时排除外部空气和水分，有利于去除挥发性有机配体和配体副产物。前体中预先形成的金属-氧键以及金属氧化态在分解过程中得以保持，形成完全化学计量的、氧化态纯净的NpO和PuO。粉末X射线衍射（PXRD）、扫描透射电子显微镜（STEM）和能量色散X射线光谱（EDS）元素映射支持了对这些高纯度材料的评估。这种化学方法适用于多种金属，包括具有可及四价氧化态的锕系元素，并为核不扩散、法医学和基础研究领域的重要分析标准提供了一条一致的途径。
