The potential energy surfaces of N2O2 species: implications for selective catalytic reduction

Stationary structures, both minima and transition states, on the potential energy surface of N2O2 have been determined using large basis sets and high levels of theory. Minima have been found at the ab initio [BD(T)] and dens ity functional theory (B3LYP) levels, and transition structures have been l ocated at the latter level. These calculations have allowed reaction pathwa ys to the formation of O-2 and N-2 to be explored. A likely initial interme diate is a non-cyclic covalently bound dimer with a barrier to formation su fficiently low to suggest that it might be a candidate for a catalytic mech anism. Subsequent steps towards N-2 and O-2 involve larger barriers, so tha t substantial catalytic activation would be required for them to be involve d in a facile reaction mechanism.