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Gas-phase experimental studies are used for studying the effect of charge state on the mechanism of CO oxidation on cationic and anionic gold clusters. The results have highlighted the role of charge state in gold-cluster-based nanocatalysis.

Near-atmospheric pressure flow reactor techniques were used to study humidity and temperature effects on the reactivity of gas-phase gold cluster anions with O2. The theory proved that electron-transfer induced by the binding of OH group enhances the reactivity toward molecular oxygen for odd anionic gold clusters and suppresses the reactivity from the even ones.

The joint theoretical and experimental results that provide evidence for the selectivity of V(sub x)O(sub y)(super +) clusters in reactions towards ethylene due to the charge and different oxidation states of vanadium for different cluster sizes are presented. It is showed that the investigation of reactions involving gas-phase cationic vanadium oxide clusters with small hydrocarbons is suitable for the identification of reactive centers responsible for selectivity in heterogeneous catalysis.

The studies have shown that a critical hydrogen transfer step required for the oxidation of ethylene and acetylene at metal oxide clusters containing radical oxygen centers is energetically favorable for cationic clusters but unfavorable for the corresponding anionic species. The extent to which various classes of reactions are promoted is affected by charge state and the cationic species as well as anionic clusters have promoted multiple cycles of carbon monoxide oxidation.

Mass spectra and kinetic measurements that reveal an unprecedented size dependence in the adsorption of multiple oxygen molecules onto anionic silver clusters are presented. These findings of coadsorption properties on Agn- clusters are conceptually important for the understanding of the role of silver clusters in oxidation processes.

Conjugation between three-dimensional (3D) carboranes and the attached substituents is commonly believed to be very weak. In this paper, we report that reducing 1,12-bis(BMes 2 )- p -carborane ( B 2 p Cab ) with one electron gives a radical anion with a centrosymmetric semiquinoidal structure. This radical anion shows extensive electron delocalization between the two boron centers over the p -carborane bridge due to the overlap of carborane lowest unoccupied molecular orbital (LUMO) and the BMes 2 LUMO. Unlike dianions of other C 2 B 10 H 12 carboranes, which rearrange to a nido -form, two-electron reduction of B 2 p Cab leads to a rearrangement into a basket-shaped intermediate.