Efficient N2 Formation on Ag(111) by Eley–Rideal Recombination of Hyperthermal Atoms

Abstract

Using molecular dynamics simulations and potential energy surfaces of ab initio quality, we show that direct pickup of N adsorbates by gas-phase N is a highly efficient channel for N2 formation on Ag(111). This recombination process, called Eley–Rideal, was traditionally associated with lighter projectiles and regarded as marginal, but here, we obtain reactivities for N of ≳35% even at incident energies of a few eV. The good agreement found between simulated and published experimental energies of the desorbed N2 is a fingerprint of this otherwise elusive recombination.