Nitrogen adsorption and hydrogenation on a MoFe_6S_9 complex

Nitrogen adsorption and hydrogenation on a MoFe_6S_9 complex

by T. H. Rod, B. Hammer, and J. K. Norskov.

Phys. Rev. Lett. 82, 4054 (1999).

Abstract

The enzyme nitrogenase catalyzes the biological nitrogen fixation where N2 is reduced to NH3. Density functional calculations are presented of the bonding and hydrogenation of H2 on a MoFe_6S_9 complex constructed to model aspects of the active site of nitrogenase. N_2 is found to bind end on to one of the Fe atoms. A complete energy diagram for the addition of hydrogen to the MoFe_6S_9 complex with and without N2 is given, and a mechanism for ammonia synthesis is proposed on this basis.