Department of Chemistry, University of Manitoba, Winnipeg, MB, Canada R3T 2N2.
J Phys Chem A. 2011 Dec 8;115(48):14110-9. doi: 10.1021/jp207556b. Epub 2011 Nov 11.
The structural properties of several plutonium(IV) and (VI) complexes have been examined in the gaseous and aqueous phases using Kohn-Sham density functional theory calculations with scalar relativistic effective core potentials and the polarizable continuum solvation model. The aquo and nitrate complexes of PuO(2)(2+) and Pu(4+) were considered in addition to the aquo-chloro complexes of PuO(2)(2+). The nitrate and chloro- complexes formed with triphenylphosphine oxide (TPPO) and tributylphosphate (TBP) respectively were also studied. The structural parameters of the plutonyl complexes were compared to their uranyl and neptunyl analogues. The bond lengths and vibrational frequencies of the plutonyl complexes can generally be computed with sufficient accuracy with the pure PBE density functional with shorter bond lengths being predicted by the B3LYP functional. The structural parameters of the [PuO(2)Cl(2)L(2)] systems formed with TPPO and TBP as well as the aqueous [PuO(2)Cl(2)(H(2)O)(3)] complex are matched to previous experimental results. Overall, the inclusion of ligands in the equatorial region results in significant changes in the stretching frequency of the plutonyl group. The structural features of the plutonyl (VI) systems are rather similar to those of their 5f(0) uranyl and 5f(1) neptunyl counterparts. For the Pu(IV) aquo and nitrate complexes, the average of the calculated Pu-OH(2) and Pu-O(nitrate) bond lengths are generally within 0.04 Å of the reported experimental values. Overall Kohn-Sham DFT can be used successfully in predicting the structures of this diverse set of Pu(VI) and Pu(IV) complexes.
使用带有标量相对论有效核势和极化连续体溶剂化模型的 Kohn-Sham 密度泛函理论计算，研究了几种镎（IV）和（VI）配合物在气相和水相中的结构性质。除了 PuO(2)(2+)的水合氯配合物外，还考虑了 PuO(2)(2+)和 Pu(4+)的水合和硝酸盐配合物。分别与三苯基氧化膦（TPPO）和三丁基磷酸酯（TBP）形成的硝酸盐和氯配合物也进行了研究。将镎氧配合物的结构参数与它们的铀酰和镎酰类似物进行了比较。镎氧配合物的键长和振动频率通常可以用纯 PBE 密度泛函足够准确地计算，而 B3LYP 函数则预测出较短的键长。用 TPPO 和 TBP 形成的 [PuO(2)Cl(2)L(2)]系统以及水合 [PuO(2)Cl(2)(H(2)O)(3)] 配合物的 [PuO(2)Cl(2)L(2)]系统的结构参数与以前的实验结果相匹配。总体而言，配体在赤道区域的加入导致镎氧基的伸缩频率发生显著变化。镎氧（VI）体系的结构特征与它们的 5f(0)铀酰和 5f(1)镎酰类似物非常相似。对于 Pu(IV)水合和硝酸盐配合物，计算得到的 Pu-OH(2)和 Pu-O（硝酸盐）键长的平均值通常与报道的实验值相差 0.04 Å 以内。总体而言，Kohn-Sham DFT 可以成功地用于预测这一系列不同的 Pu(VI)和 Pu(IV)配合物的结构。
