Thermochemical characterization of seaborgium compounds in gas adsorption chromatography

The chemical characterization of the element seaborgium (Z = 106) requires fast experiments such as gas adsorption chromatographic separations in quartz columns with single atoms in a clearly defined chemical state. The maximum separation time for such experiments of only about 10 s is defined by the relatively short half-lives of the currently known longest-lived isotopes (265)Sg and (266)Sg. To establish optimum experimental parameters, the required thermochemical quantities for chlorides, oxychlorides, and oxides of seaborgium were estimated by extrapolation. On the basis of these results, the stability and volatility of these compounds could be calculated. By use of empirical correlations, the thermochemical constants of the adsorption precesses were evaluated and the retention times calculated, taking into account the composition of the reactive carrier gas. The dioxydichloride of seaborgium proved to be the most suitable chemical state regarding its stability, volatility, and retention. Its standard sublimation enthalpy is expected to be between 125 and 144 kJ/mol (larger than that of WO2Cl2), resulting in an adsorption enthalpy between -97 and -108 kJ/mol. If the chemistry of seaborgium significantly deviates from the above predicted behavior, then this could be attributed to the possible influence of relativistic effects.