The impact of the properties of the heaviest elements on the chemical and physical sciences
The impact of the properties of the heaviest elements on the chemical and physical sciences
复制标题
最重元素的性质对化学和物理科学的影响
DOI：
10.1524/ract.2012.1963
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发表时间：
2012
影响因子：
1.8
通讯作者：
J. Kratz
中科院分区：
文献类型：
--
作者：
J. Kratz
讨论了重元素在化学和物理科学中的独特作用。对于锕系元素（Z = 90-103）和超锕系元素（Z = 122-155），最重的元素显著地塑造了元素周期表的结构。最重元素的电子层中的相对论效应以非线性方式改变给定基团的化学性质。相对论稳定的次壳层封闭物在周期表中产生了一类新的元素：挥发性金属。这种性质的原型是元素114，由于其7s 2 7 p21/2电子构型的相对论稳定性，在其基本状态下是挥发性的，但与稀有气体相反，在室温下与金表面表现出明显的金属-金属相互作用。核壳层效应决定了超铀元素的物理性质。这导致了锕系元素（U-Bk）的超形变形状异构体（裂变异构体）。超重元素（Z ≥ 104）在N = 152、162和184时的存在完全是由于核壳效应。在这个时候，一个建筑群是下一个球形质子壳层关闭的位置，因为有证据表明“稳定岛”的中心不在Z = 114。这迫切需要进一步的理论和实验努力。元素119和120的合成截面将为我们提供关于“元素周期表上端”的重要信息。
Abstract The unique role of the heaviest elements in chemical and physical sciences is discussed. With the actinide series (Z = 90-103) and the superactinide series (Z = 122-155), the heaviest elements have significantly shaped the architecture of the Periodic Table of the elements. Relativistic effects in the electron shells of the heaviest elements change the chemical properties in a given group in a non-linear fashion. Relativistically stabilized sub-shell closures give rise to a new category of elements in the Periodic Table: volatile metals. The prototype for this property is element 114 which, due to the relativistic stabilization of its 7s2 7p21/2 electron configuration, is volatile in its elementary state, but, in contrast to a noble gas, exhibits a marked metalmetal interaction with a gold surface at room temperature. Nuclear shell effects dominate the physical properties of the transuranium elements. These give rise to superdeformed shape isomers (fission isomers) in the actinides (U-Bk). Superheavy elements (Z ≥ 104) owe their existence solely to nuclear shell effects at N = 152, 162, and 184. At this time, a building lot is the location of the next spherical proton shell closure as there is evidence that the center of the “island of stability” is not at Z = 114. This needs urgently further theoretical and experimental efforts. The cross sections for the syntheses of elements 119 and 120 will give us important information on the “upper end of the Periodic Table of the elements”.