By means of the electronic confined space analogy (ECSA), the (4
n+2) π Hü
ckel rule, as followed by 2D aromatic [
n]annulenes, has been connected to the 3D aromatic Wade-Mingos’ rule found for
closo [B
nH
n]
2- clusters. Application of the ESCA method to medium and large boron clusters allows their classification into different series according to the
n value of the Hü
ckel (4
n+2) π rule (photo credit: Iñaqui Sanjuán Pertusa). More information can be found in the Full Paper by M. Solá, F. Teixidor et al. on
page 7437 ff.