Pershina Valeria
GSI Helmholtzzentrum für Schwerionenforschung GmbH , Planckstr. 1 , 64291 Darmstadt , Germany.
Inorg Chem. 2018 Apr 2;57(7):3948-3955. doi: 10.1021/acs.inorgchem.8b00101. Epub 2018 Mar 22.
Adsorption energies of superheavy elements (SHEs) Cn, Nh, and Fl and their lighter homologues Hg, Tl, and Pb, respectively, on a Au(111) surface at different adsorbate coverages are predicted via periodic relativistic DFT calculations with the aim of assisting the outcome of related "one-atom-at-a-time" gas-phase chromatography experiments. In agreement with previous DFT studies with the use of a cluster model, the present results for large supercells are indicative of high volatility of Cn. Thus, this element should not interact with the regular Au(111) surface at room temperature but should adsorb on it in a vacancy. Fl should moderately interact with such a surface under ambient conditions, while Nh should be the most reactive element with respect to gold. All three elements should, however, reveal much lower reactivity toward gold than their lighter homologues. The reasons for this are the strong relativistic stabilization and contraction of the 7s and 7p AOs. The obtained trend in the adsorption energy, Nh ≫ Fl > Cn, enables one to easily separate these elements from each other, as well as from their lighter homologues using gold or gold/quartz surfaces.
通过周期性相对论密度泛函理论(DFT)计算,预测超重元素(SHEs)Cn、Nh和Fl及其较轻的同系物Hg、Tl和Pb在不同吸附质覆盖度下在Au(111)表面的吸附能,目的是辅助相关“一次一个原子”气相色谱实验的结果。与先前使用团簇模型的DFT研究一致,大型超胞的当前结果表明Cn具有高挥发性。因此,该元素在室温下不应与常规的Au(111)表面相互作用,而应吸附在空位上。在环境条件下,Fl应与这样的表面适度相互作用,而Nh相对于金应是最具反应性的元素。然而,所有这三种元素对金的反应性应比其较轻的同系物低得多。其原因是7s和7p原子轨道的强相对论稳定化和收缩。所获得的吸附能趋势Nh≫Fl>Cn,使得能够使用金或金/石英表面轻松地将这些元素彼此分离,以及与它们较轻的同系物分离。