Overdestabilization vs Overstabilization in the Theoretical Analysis of f-Orbital Covalency
Overdestabilization vs Overstabilization in the Theoretical Analysis of f-Orbital Covalency
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DOI：
10.1021/jacs.4c01665
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发表时间：
2024-04-22
影响因子：
15
通讯作者：
Li，Xiaosong
中科院分区：
文献类型：
--
作者：
Shumilov，Kirill D.;Jenkins，Andrew J.;Li，Xiaosong
f轨道电子结构的复杂性及其与化学环境的相互作用构成了重大的计算挑战。先进的计算技术，变包括标量相对论和自旋轨道耦合直接在分子轨道水平已经开发，以解决这个复杂性。其中，变分相对论多构型多参考方法在f-区配合物研究中以其高精度和系统性的改进而脱颖而出。此外，这些先进的方法提供了校准低尺度电子结构方法，如密度泛函理论的潜力。然而，对[Ce（III）Cl 6]3-和[Ce（IV）Cl 6]2-络合物的Cl K边X射线吸收光谱的研究表明，具有近似交换相关核的含时密度泛函理论可能导致不准确，导致4f轨道的过度稳定和共价性的不正确评估。相比之下，利用小主动空间波函数方法的方法可能低估这些轨道的稳定性。本文的结果表明，需要大的活性空间，多参考，和变分相对论方法在研究f-块配合物。
The complex nature of the f-orbital electronic structures and their interaction with the chemical environment pose significant computational challenges. Advanced computational techniques that variationally include scalar relativities and spin–orbit coupling directly at the molecular orbital level have been developed to address this complexity. Among these, variational relativistic multiconfigurational multireference methods stand out for their high accuracy and systematic improvement in studies of f-block complexes. Additionally, these advanced methods offer the potential for calibrating low-scaling electronic structure methods such as density functional theory. However, studies on the Cl K-edge X-ray absorption spectra of the [Ce(III)Cl6]3–and [Ce(IV)Cl6]2–complexes show that time-dependent density functional theory with approximate exchange–correlation kernels can lead to inaccuracies, resulting in an overstabilization of 4f orbitals and incorrect assessments of covalency. In contrast, approaches utilizing small active space wave function methods may understate the stability of these orbitals. The results herein demonstrate the need for large active space, multireference, and variational relativistic methods in studying f-block complexes.