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Adsorption properties of group 1 and 2 elements Cs, Fr and E119 and Ba, Sr and E120, respectively, and of group 1 hydrides and hydroxides on hydroxylated quartz surfaces were calculated using a periodic relativistic DFT approach. The results show that all the considered group 1 and 2 elements should adsorb rather moderately on the quartz surfaces, with E119 and E120 most weakly, due to the strong relativistic stabilisation and contraction of the 8s atomic orbital. This means that E119 and E120 should have a deposition peak in the quartz chromatography column with a temperature gradient from room temperature to far below zero in the sequence Cs/Ba > Fr/Ra > E119/E120. For group 1 element MH and MOH, the adsorption energies are high, so that the adsorption–desorption equilibrium should be reached at very high temperatures, with the following trend in the adsorption strength MH > MOH >> M. Relativistic periodic DFT calculations of the adsorption properties of group 1 and 2 elements, including elements 119 and 120, and of their hydrides and hydroxides, on the hydroxylated quartz surfaces. [ABSTRACT FROM AUTHOR]

Adsorption energies, Eads, of oxides and oxyhydrides of the superheavy element (SHEs) Ts and of its lighter homologue At on the gold surface are predicted on the basis of relativistic periodic density functional theory calculations via AMS BAND software. The following compounds were considered: MO, MO2, MOO, and MO(OH) (where M = At and Ts). The aim of this study is to support "one-atom-at-a-time" gas-phase chromatography experiments on reactivity/volatility of SHEs. The results obtained indicate that all the molecules investigated should interact fairly strongly with the gold surface, with those of Ts being more reactive than At ones. The similarity in the Eads values of all the considered At compounds would make it challenging to differentiate between them while measuring their adsorption enthalpies, given experimental uncertainty. However, the difference in Eads among Ts compounds is more pronounced, so that one should be able to differentiate between the species. [ABSTRACT FROM AUTHOR]

Adsorption energies, Eads, of the 7th row superheavy elements (SHEs) Lv through Og, as well as of the homologous species of the 6th row elements Po through Rn on a gold surface are predicted on the basis of relativistic periodic density functional theory calculations via SCM BAND software. Since some of the elements can also form compounds such as hydrides and oxyhydrides under experimental conditions, the Eads values of the MH (M = Bi/Mc, Po/Lv, At/Ts and Rn/Og) and MOH (M = At/Ts and Rn/Og) molecules on a gold surface were also calculated. The aim of this study is to support "one-atom-at-a-time" gas-phase chromatography experiments on the reactivity/volatility of SHEs. The obtained results show that, in agreement with earlier predictions using somewhat different approaches and with experimental results on Hg, Cn and Rn, the adsorption strength of the elements on the Au(111) surface should follow the sequence: Hg > Fl > Og > Cn ≫; Rn, with the Eads values of less than 100 kJ mol−1. The other elements and their compounds under consideration should adsorb much more strongly on the gold surface with Eads values above 160 kJ mol−1, which should make them indistinguishable with respect to Eads in the chromatography column kept at room temperature and lower. However, with the further detector development, investigations of the chemical properties of these short-lived and less volatile SHEs and their compounds at high temperatures should be possible. [ABSTRACT FROM AUTHOR]

Superheavy element research has been a strong pillar of the research program at GSI Darmstadt since its foundation. Six new elements were discovered along with many new isotopes. Initial results on chemical properties of the heaviest elements were obtained that allowed for comparing their behavior with that of their lighter homologs and with theoretical predictions. Main achievements of the past five decades of superheavy element research at GSI are described along with an outlook into the future of superheavy element research in Darmstadt. [ABSTRACT FROM AUTHOR]

Adsorption energies, Eads, and other properties of atoms and oxides of the superheavy elements (SHEs) Cn and Fl, as well as of the homologous species of Hg and Pb, on Au(111) and fully hydroxylated quartz surfaces are predicted on the basis of 2c-DFT calculations and a periodic slab model using BAND software. The ambition of the work is to interpret the outcome of "one-atom-at-a-time" gas-phase chromatography experiments on the reactivity/volatility of SHEs. The present results with an improved (dispersion corrected) exchange--correlation functional show that, in agreement with our earlier predictions and experimental results on Pb, Hg and Cn, the sequence of the Eads values of the atoms on the gold surface should be Pb > Hg > Fl > Cn, with rather moderate Eads values smaller than 90 kJ mol-1 (except for that for Pb). Oxides of Hg, Cn and Fl should be much more reactive with the gold surface than the corresponding atoms, with Eads values of about 200 kJ mol-1. A striking difference in the geometry of the deposited oxides was found between group 12 and group 14. An analysis of the Eads values for M and MO (M = Hg/Cn and Pb/Fl) on the hydroxylated α-quartz surface enables one to conclude that atoms of Hg, Cn and Fl should not interact with such a surface at room temperature, while Pb should adsorb on it. Oxides of these elements, on the contrary, should strongly adsorb on quartz with Eads ≥ 100 kJ mol-1. The present theoretical data agree with the experimental results on the elemental species of Hg, Cn and Fl. [ABSTRACT FROM AUTHOR]

Theoretical chemical studies demonstrated crucial importance of relativistic effects in the physics and chemistry of superheavy elements (SHEs). Performed, with many of them, in a close link to the experimental research, those investigations have shown that relativistic effects determine periodicities in physical and chemical properties of the elements in the chemical groups and rows of the Periodic Table beyond the 6th one. They could, however, also lead to some deviations from the established trends, so that the predictive power of the Periodic Table in this area may be lost. Results of those studies are overviewed here, with comparison to the recent experimental investigations. [ABSTRACT FROM AUTHOR]