Activation of Small Molecules by Modified Dodecaborate Anions

Two of the basic requirements of a good catalyst are that molecules be bound to it with energies intermediate between physisorption and chemisorption and be simultaneously activated in the process. Using density functional theory, we have studied the interaction of small molecules such as H-2, O-2, N-2, CO2, CO, and NH3 with modified dodecaborate anion [B12H12](2-), namely, [B12X11](-) and [B12X11](2-) (X = H, F, CN). Calculations of the structure, stability, and electronic properties of these species interacting with the above molecules show that they meet the above requirements. In addition, [B12X11](2-) (X = F, CN) species are not only more stable than [B12X11](-) species but also bind to O-2 more strongly than their monoanion counterparts.