Trombach Lukas, Ehlert Sebastian, Grimme Stefan, Schwerdtfeger Peter, Mewes Jan-Michael
Centre for Theoretical Chemistry and Physics, The New Zealand Institute for Advanced Study, Massey University Auckland, Private Bag 102904, 0632 Auckland, New Zealand.
Phys Chem Chem Phys. 2019 Aug 21;21(33):18048-18058. doi: 10.1039/c9cp02455g.
The design, implementation, and evaluation of a computationally efficient approach for exploring the chemical nature and bulk properties of the super-heavy main-group elements (SHEs) Cn-Og with nuclear charges of Z = 112-118 is described. The approach combines plane-wave density-functional theory (DFT) based on a newly devised set of projector-augmented wave potentials (PAWs) with the D3 dispersion correction, whose parameter-space is extended for this purpose. Regarding both, the fitting of the PAWs as well as the calculation of the D3 parameters, it is shown that the peculiar electronic structure of the SHEs with strong relativistic effects makes it necessary to adapt the well established computational protocols. Eventually, the methodology is tested employing various common functionals (PW91, PBE, PBE-D3, PBE0-D3, PBEsol and SCAN) by comparison to experimental and high-level results for the bulk of Cn and Og, as well as by calculating adsorption energies of Cn-Og on a gold surface and comparing these to the lighter congeners Hg-Rn as well as experimentally derived data. These tests establish that our approach provides a consistent and accurate description of the reactivity of the SHEs and is largely in excellent agreement with experimental and high-level references, and moreover underline the great relevance of dispersion interactions, as well the game-changing impact of spin-orbit coupling on SHE reactivity. Ultimately, the conducted calculations provide novel insights into the chemical behavior and nature of the SHEs, showcase the breakdown of periodic trends in the seventh period, and allow us to revisit and confirm an empirical relation between adsorption on gold and the cohesive energy.
本文描述了一种计算效率高的方法的设计、实施和评估，该方法用于探索核电荷数Z = 112 - 118的超重主族元素（SHEs）Cn - Og的化学性质和体相性质。该方法将基于一组新设计的投影增强波势（PAWs）的平面波密度泛函理论（DFT）与D3色散校正相结合，为此扩展了其参数空间。关于PAWs的拟合以及D3参数的计算，结果表明，具有强相对论效应的SHEs的特殊电子结构使得有必要调整已确立的计算协议。最终，通过与Cn和Og体相的实验结果和高水平结果进行比较，以及通过计算Cn - Og在金表面的吸附能并将其与较轻的同系物Hg - Rn以及实验得出的数据进行比较，使用各种常用泛函（PW91、PBE、PBE - D3、PBE0 - D3、PBEsol和SCAN）对该方法进行了测试。这些测试表明，我们的方法能够对SHEs的反应性提供一致且准确的描述，并且在很大程度上与实验和高水平参考文献高度吻合，此外还强调了色散相互作用的重要性，以及自旋轨道耦合对SHEs反应性的变革性影响。最终，所进行的计算为SHEs的化学行为和性质提供了新的见解，展示了第七周期中周期趋势的中断，并使我们能够重新审视并确认金吸附与内聚能之间的经验关系。
