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Density Functional Theory and Complete Active Space Self-Consistent Field (CASSCF) methodologies are used to explore the electronic structure of the cationic V–N clusters, [V₄N₄]⁺ and [V₆N₆]⁺, that have been identified in recent mass spectrometric experiments. Our calculations indicate that both clusters are based on cubane-like fragments of the rock-salt lattice. In the smaller [V₄N₄]⁺ cluster, the V–V bonding is delocalized over the tetrahedron, with net bond orders of 1/3 per V–V bond. In [V₆N₆]⁺, in contrast, the V–V bonding is strongly localized in the central V₂N₂ unit, which has a short V=V double bond. CASSCF calculations reveal that both localized and delocalized V–V bonds are highly multi-configurational.