Reiher Markus, Hirsch Andreas
Theoretische Chemie, Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen, Germany.
Chemistry. 2003 Nov 21;9(22):5442-52. doi: 10.1002/chem.200304812.
The characteristic features of molecules like polyhedra and fullerenes, which follow the 2(N+1)(2) rule of spherical aromaticity, can be related to energetically stable closed-shell configurations of (pseudo-)atoms. This unifying view relies on a thought experiment, which produces a polyhedron in a two-step process and which can, in turn, relate the electronic configuration of any spherical polyhedron to the one of a corresponding closed-shell atom. In the first step, the electronic ground-state configuration is identified. In the second step, a group theoretical analysis can be carried out; this relates the spherically symmetric atomic orbitals to the molecular orbitals classified according to the irreducible representations of the point group of the polyhedron under consideration. This procedure explains and justifies the pseudo-l classification of molecular orbitals, which is the basis of the 2(N+1)(2) rule. For the transition from the electronic configuration of the rare gas Eka-Rn (Uuo) to the icosahedral fullerene C(20) (2+), we show how a change in the ground-state configuration leads to the phenomenologically found 2(N+1)(2) rule for spherically aromatic fullerenes.
像多面体和富勒烯这样的分子具有特征特性，它们遵循球形芳香性的2(N + 1)²规则，这可以与（准）原子的能量稳定闭壳层构型相关联。这种统一的观点依赖于一个思想实验，该实验通过两步过程生成一个多面体，进而可以将任何球形多面体的电子构型与相应闭壳层原子的电子构型联系起来。第一步，确定电子基态构型。第二步，可以进行群论分析；这将球对称原子轨道与根据所考虑多面体的点群的不可约表示分类的分子轨道联系起来。这个过程解释并证明了分子轨道的准l分类，这是2(N + 1)²规则的基础。对于从稀有气体类氡（Uuo）的电子构型到二十面体富勒烯C₂₀²⁺的转变，我们展示了基态构型的变化如何导致从现象学上发现的球形芳香性富勒烯的2(N + 1)²规则。
