Hybrid density functional theory study of hydrogen cluster aromaticity by computing their relative energies and magnetic properties

Magnetic properties and energies of linear and planar hydrogen clusters in their singlet and triplet electronic states were computed with the B3LYP hy brid density functional theory method. The energy of cyclization and change of magnetic properties in the course of cyclization of isoelectronic hydro gen clusters were used as criteria for aromaticity of these hydrogen cluste rs. Although only sigma-electrons were involved, it was demonstrated that s tability, as well as the change of magnetic properties in the singlet elect ronic state follow Huckel's rule, while in their triplet electronic state t hey follow Mobius' aromatic rule. (C) 1999 John Wiley & Sons, Inc.