The pseudo‐element concept, in its most general formulation, states that isoelectronic atoms form equal numbers of bonds. Hence, clusters such as Zintl ions usually retain their structure upon isoelectronic replacement of some or all atoms. Here, a deviation from this common observation is presented, namely the formation of (Sn₅Sb₃)³⁻ (1 ), a rare example of an eight‐vertex Zintl ion, and an unprecedented example of a Zintl ion synthesized by solution means that has an arachno‐type structure according to the Wade–Mingos rules. Three structure‐types of interest for (Sn₅Sb₃)³⁻ were identified by DFT calculations: one that matched the X‐ray diffraction data, and two that that were reminiscent of fragments of known clusters. A study on the isoelectronic series of clusters, (Sn_xSb_8−x)^2−x (x=0–8), showed that the relative energies of these three isomers vary significantly with composition (independent of electron count) and that each is the global minimum at least once within the series.

中文翻译：

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Arachno-Zintl离子（Sn5 Sb3）3-和元素组成对等电子簇结构的影响：伪元素概念的另一个方面。

伪元素概念在其最笼统的表述中指出，等电子原子形成相等数量的键。因此，诸如Zintl离子之类的簇通常在一些或所有原子的等电取代后保持其结构。在这里，提出了与该常规观察结果的偏差，即（Sn ₅ Sb ₃）^3-（1）的形成，八顶点Zintl离子的罕见实例和通过溶液法合成的Zintl离子的前所未有的实例根据Wade–Mingos规则具有蛛网类型的结构。（Sn ₅ Sb ₃）³⁻的三种感兴趣的结构类型通过DFT计算可以确定：一种与X射线衍射数据匹配，另一种与已知簇的碎片相似。对（Sn _x Sb _8-x）^{2 -x}（x = 0–8）的团簇等电子序列的研究表明，这三种异构体的相对能量随组成（与电子数无关）而显着变化。是系列中至少一次的全局最小值。