Are the Dmh Symmetric Hxq Rings with 4n + 2 σ-Electrons and Hydrogen Clusters Aromatic?

The Dmh symmetric Hxq rings, H5- (D5h, D4h), H5+ (C2v), H6 (D6h, D5h), H7+ (D7h, D6h), H82+/2- (D8h), H9+ (D3h), H9- (D9h, D8h), and H10 (D10h, D9h) are considered as possible analogs of the Huckel 4n + 2 electron aromatic annulene systems. While aromatic character (due to ring current effects) is indicated by the magnetic susceptibility exaltations (Λ) and large magnetic susceptibility anisotropies, χanis (derived from IGLO computations of the magnetic properties), most of these hydrogen ring systems are higher order saddle points. The exceptions are transition structures:  H6 (D6h), which can be compared with benzene, and H10 (D10h) which is even less favorable energetically. On the basis of energetic, structural, and magnetic criteria, aromaticity can result from cyclic delocalization of σ- as well as π-electrons. On the basis of the diamagnetic exaltations, “spherical aromaticity” is illustrated by H62- and H8, both with Oh symmetry and eight σ-electrons as well as H42+ with Td symmetry and only two σ...