Institut de Química Computacional and Departament de Química, Universitat de Girona, Campus de Montilivi, 17071 Girona, Spain.
Chem Commun (Camb). 2011 Nov 14;47(42):11647-9. doi: 10.1039/c1cc14958j. Epub 2011 Sep 27.
4N Baird's rule represented the extension of Hückel's 4N + 2 rule to triplet state systems. In this work we extend the 2(N + 1)(2) Hirsch rule for spherical aromatic species to open-shell spherical compounds and we provide evidence that those spherical species having a same-spin half-filled last energy level with the rest of the levels being fully-filled, i.e., those having 2N(2) + 2N + 1 electrons and S = N + ½, are aromatic.
4N 贝尔德规则代表了休克尔的 4N+2 规则向三重态体系的扩展。在这项工作中，我们将球形芳香族物种的 2（N+1）（2）赫希规则扩展到开壳层球形化合物，并提供证据表明那些具有与其余能级完全填充的自旋相同的半满最后能级的球形物种，即具有 2N(2)+2N+1 个电子和 S=N+½，是芳香族的。
