Disk Aromaticity of the Planar and Fluxional Anionic Boron Clusters B20−/2−

Abstract

The presence of excess electrons modifies the structural landscape and tends to extend the planarity of boron clusters. While the neutral B(20) is tubular, both the anion and dianion B(20)(-/2-) become planar. Geometrical features of the stable anions suggest the existence of a new type of cluster that is planar and doubly cyclic with one atom located at the center (see figure), as well as being fluxional.