Theoretical study of CO oxidation on small gold cluster anions: Role of the carbonate adducts

CO oxidation on Au 2 n - (n = 1 – 4) cluster anions are investigated using DFT methods. O2 prefers to bind on-top to a gold atom. Binding energies of O2 on Au 2 n - are in the range of 0.8–1.2 eV. CO molecule can then insert into the O–O bond of Au 2 n O 2 - to form carbonate species, that are the most stable Au 2 n CO 3 - isomers, and thus expected to play an important role in CO oxidation. The negative charges of the gold carbonates are mainly distributed on the CO3 moieties. The gold carbonate anions can yield CO2 by direct dissociation or react with another CO to produce 2(CO2).