STRUCTURE OF V(H-2)(N)(+) CLUSTERS FOR N=1-6

Geometries, vibrational frequencies, spin states, H-2 binding energies, and Delta S values have been determined for V(H-2)(n)(+), for It = 1-6, using the B3LYP hybrid functional. The binding energies and Delta S values are in good agreement with experiment, thus showing that the B3LYP functional offers a reliable approach for optimizing the geometry and determining the H-2 binding energies for this system. The calculations show that the increase in the binding energy and entropy associated with the addition of the sixth H-2 to V+ is due to a change in spin state from quintet for the smaller clusters to triplet for V(H-2)(6)(+). The results for V(H-2)(n)(+) are compared with those for Co(H-2)(n)(+).