Infrared spectroscopy of V2+(H2O) complexes

Doubly charged vanadium–water complexes are produced by laser vaporization in a pulsed supersonic expansion. Size-selected ions are studied with infrared photodissociation spectroscopy in the O–H stretch region using argon complex predissociation. Density functional theory calculations provide structures and vibrational spectra of these ions. The O–H stretches of V2+(H2O) appear at lower frequencies than those of the free water molecule or V+(H2O). The symmetric stretch is more intense than the asymmetric stretch in both V+(H2O) and V2+(H2O) complexes. Spectra of V2+(H2O)Arn (n = 2–7) show that the coordination of the V2+ is filled with six ligands, i.e. one water and five argon atoms.