Interaction of vanadium oxide cluster anions with water: an experimental and theoretical study on reactivity and mechanism.

Vanadium oxide cluster anions (V(x)O(y)(-), x = 2-3; y = 3-7) are produced by laser ablation and reacted with water in a fast flow reactor. A time-of-flight mass spectrometer is used to detect the cluster distribution before and after the reactions. Reaction channels of molecular hydrogen elimination (for V(2,3)O(3)(-)), water association (for V(2)O(5)(-) and V(3)O(6,7)(-)) and the coexistence of both channels (for V(2)O(4)(-) and V(3)O(4,5)(-)) are observed. V(2)O(6)(-) and V(3)O(8)(-) are nearly inert toward water. Density functional theory (DFT) calculations are performed to study the reaction mechanism of V(2)O(3)(-) in different spin states with water and the results support the experimental observation. The reaction mechanism of V(2)O(3)(+) with water is also studied, which is in agreement with the experimental report in previous literature [Eur. J. Inorg. Chem., 2008, 4961] that molecular hydrogen elimination is a minor reaction channel for V(2)O(3)(+) + H(2)O. The influence of cluster charge states and oxidation states of vanadium atoms on the cluster reactivity are presented based on the experimental and theoretical studies.