European Commission, Joint Research Centre , P.O. Box 2340, 76125 Karlsruhe , Germany.
Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 United States.
Inorg Chem. 2018 Aug 6;57(15):9453-9467. doi: 10.1021/acs.inorgchem.8b01450. Epub 2018 Jul 24.
Pentavalent actinyl nitrate complexes AnO(NO) were produced by elimination of two NO from An(NO) for An = Pu, Am, Cm, Bk, and Cf. Density functional theory (B3LYP) and relativistic multireference (CASPT2) calculations confirmed the AnO(NO) as AnO actinyl moieties coordinated by nitrates. Computations of alternative AnO(NO) and AnO(NO) revealed significantly higher energies. Previous computations for bare AnO indicated AnO for An = Pu, Am, Cf, and Bk, but CmO: electron donation from nitrate ligands has here stabilized the first Cm complex, CmO(NO). Structural parameters and bonding analyses indicate increasing An-NO bond covalency from Pu to Cf, in accordance with principles for actinide separations. Atomic ionization energies effectively predict relative stabilities of oxidation states; more reliable energies are needed for the actinides.
五价锕系元素硝酸根配合物 AnO(NO) 通过从 An(NO) 中消除两个 NO 生成，其中 An = Pu、Am、Cm、Bk 和 Cf。密度泛函理论 (B3LYP) 和相对论多参考 (CASPT2) 计算证实，AnO(NO) 中 AnO 为锕系元素的活性氧部分，由硝酸根配位。对替代的 AnO(NO) 和 AnO(NO) 的计算表明，能量显著升高。以前对裸露的 AnO 的计算表明，对于 An = Pu、Am、Cf 和 Bk，存在 AnO，但 CmO：硝酸盐配体的电子给予在此稳定了第一个 Cm 配合物，即 CmO(NO)。结构参数和键分析表明，随着从 Pu 到 Cf 的增加，An-NO 键的共价性增加，这符合锕系元素分离的原则。原子电离能可有效预测氧化态的相对稳定性；对于锕系元素，需要更可靠的能量。
