Berryman Victoria E J, Shephard Jacob J, Ochiai Tatsumi, Price Amy N, Arnold Polly L, Parsons Simon, Kaltsoyannis Nikolas
Department of Chemistry, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
Phys Chem Chem Phys. 2020 Aug 7;22(29):16804-16812. doi: 10.1039/d0cp02947e. Epub 2020 Jul 14.
Covalency is complex yet central to our understanding of chemical bonding, particularly in the actinide series. Here we assess covalency in a series of isostructural d and f transition element compounds M(OCH) (M = Ti, Zr, Hf, Ce, Th, Pa, U, Np) using scalar relativistic hybrid density functional theory in conjunction with the Natural Bond Orbital (NBO), quantum theory of atoms in molecules (QTAIM) and interacting quantum atoms (IQA) approaches. The IQA exchange-correlation covalency metric is evaluated for the first time for actinides other than uranium, in order to assess its applicability in the 5f series. It is found to have excellent correlation with NBO and QTAIM covalency metrics, making it a promising addition to the computational toolkit for analysing metal-ligand bonding. Our range of metrics agree that the actinide-oxygen bonds are the most covalent of the elements studied, with those of the heavier group 4 elements the least. Within the early actinide series, Th stands apart from the other three elements considered, being consistently the least covalent.
共价性复杂但对于我们理解化学键，尤其是在锕系元素中，至关重要。在此，我们使用标量相对论杂化密度泛函理论结合自然键轨道（NBO）、分子中原子量子理论（QTAIM）和相互作用量子原子（IQA）方法，评估了一系列同构的d和f过渡元素化合物M(OCH)（M = Ti、Zr、Hf、Ce、Th、Pa、U、Np）中的共价性。首次对除铀以外的锕系元素评估了IQA交换相关共价性度量，以评估其在5f系列中的适用性。发现它与NBO和QTAIM共价性度量具有极好的相关性，使其成为分析金属-配体键合的计算工具包中有前景的补充。我们的一系列度量一致认为，在研究的元素中，锕系元素与氧的键是最具共价性的，而较重第4族元素的键共价性最小。在早期锕系元素系列中，钍与所考虑的其他三种元素不同，始终是共价性最小的。
