First-Principles Study of Structural, Electronic and Magnetic Properties of Metal-Centered Tetrahexahedral V15⁺ Cluster.

The V-centered bicapped hexagonal antiprism structure (A), as the most stable geometry of the cationic V15⁺ cluster, is determined by using infrared multiple photo dissociation (IR-MPD) in combination with density functional theory computations. It is found that the A structure can be stabilized by 18 delocalized 3c-2e σ-bonds on outer V₃ triangles of the bicapped hexagonal antiprism surface and 12 delocalized 4c-2e σ-bonds on inner trigonal pyramidal V₄ moiety, and the features are related to the strong p-d hybridization of the cluster. The total magnetic moments on the cluster are predicted to be 2.0 µB, which come mainly from the central vanadium atom.