GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Planckstr. 1, D-64291 Germany.
J Chem Phys. 2012 Apr 7;136(13):134317. doi: 10.1063/1.3699232.
Trends in properties of group-2 elements Ca through element 120 and their M(2) and MAu dimers were determined on the basis of atomic and molecular relativistic density functional theory calculations. The relativistic contraction and stabilization of the ns AO with increasing atomic number were shown to result in the inversion of trends both in atomic and molecular properties in group 2 beyond Ba, so that element 120 should be chemically similar to Sr. Due to the same reason, bonding in (120)(2) and 120Au should be the weakest among the considered here M(2) and MAu. Using calculated dissociation energies of M(2), the sublimation enthalpy, ΔH(sub), of element 120 of 150 kJ/mol was estimated via a correlation between these quantities in group 2. Using the M-Au binding energies, the adsorption enthalpies, ΔH(ads), of element 120 of 172 kJ/mol on gold, 127 kJ/mol on platinum, and 50 kJ/mol on silver were estimated via a correlation with known ΔH(ads) in the group. These moderate values of ΔH(ads) are indicative of a possibility of chromatography adsorption studies of element 120 on these noble metal surfaces.
基于原子和分子相对论密度泛函理论计算，确定了第 2 族元素 Ca 到第 120 号元素及其 M(2)和 MAu 二聚体的性质趋势。随着原子序数的增加，nsAO 的相对论收缩和稳定化导致第 2 族中 Ba 之后的原子和分子性质趋势发生反转，因此 120 号元素在化学上应该与 Sr 相似。由于同样的原因，(120)(2)和 120Au 中的键合应该是这里考虑的 M(2)和 MAu 中最弱的。通过在第 2 族中这些量之间的相关性，使用计算的 M(2)的离解能，估计了 120 号元素的升华焓 ΔH(sub)为 150 kJ/mol。使用 M-Au 结合能，通过与已知第 2 族中的 ΔH(ads)的相关性，估计了 120 号元素在金上的吸附焓 ΔH(ads)为 172 kJ/mol，在铂上为 127 kJ/mol，在银上为 50 kJ/mol。这些适度的 ΔH(ads)值表明 120 号元素在这些贵金属表面上进行色谱吸附研究的可能性。
