GSI Helmholtzzentrum für Schwerionenforschung, Planckstr. 1, D-64291 Darmstadt, Germany.
J Chem Phys. 2013 May 7;138(17):174301. doi: 10.1063/1.4802765.
Fully relativistic, four-component density functional theory electronic structure calculations were performed for M(CO)6 of group-6 elements Cr, Mo, W, and element 106, Sg, with an aim to predict their adsorption behaviour in the gas-phase chromatography experiments. It was shown that seaborgium hexacarbonyl has a longer M-CO bond, smaller ionization potential, and larger polarizability than the other group-6 molecules. This is explained by the increasing relativistic expansion and destabilization of the (n - 1)d AOs with increasing Z in the group. Using results of the calculations, adsorption enthalpies of the group-6 hexacarbonyls on a quartz surface were predicted via a model of physisorption. According to the results, -ΔHads should decrease from Mo to W, while it should be almost equal--within the experimental error bars--for W and Sg. Thus, we expect that in the future gas-phase chromatography experiments it will be almost impossible--what concerns ΔHads--to distinguish between the W and Sg hexacarbonyls by their deposition on quartz.
采用完全相对论性、四分量密度泛函理论对第 6 族元素 Cr、Mo、W 和 106 号元素 Sg 的 M(CO)6（M 代表元素）进行了电子结构计算，目的是预测它们在气相色谱实验中的吸附行为。结果表明，锝六羰基的 M-CO 键更长，电离势更小，极化率更大，这可以用随着族中 Z 的增加，（n-1）d AOs 的相对论性膨胀和不稳定性增加来解释。利用计算结果，通过物理吸附模型预测了第 6 族六羰基化合物在石英表面上的吸附焓。结果表明，-ΔHads 应该从 Mo 到 W 减小，而对于 W 和 Sg，它应该几乎相等——在实验误差范围内。因此，我们预计在未来的气相色谱实验中，几乎不可能——就 ΔHads 而言——通过它们在石英上的沉积来区分 W 和 Sg 的六羰基化合物。
