Coverage dependence of N2 dissociation at N, O, or H precovered Ru(0001).
Coverage dependence of N2 dissociation at N, O, or H precovered Ru(0001).¶
by B. Hammer.
Phys. Rev. B, 63, 205423 (2001).
The coverage dependence of the dissociative N2 adsorption reaction at a precovered Ru(0001) surface is investigated by means of density functional theory calculations. The energy barrier for N2 dissociation increases with the N or O precoverage and to a lesser extent with the H precoverage. The stability of the reaction products, 2N, decreases monotonically with the precoverage. The coverage dependent Ru 4d-band center in energy, epsilon_d, at the reaction site, is shown to control the energy barrier and reaction energy. The results are thereby explained in terms of a substrate mediated interaction between the dissociating N2 and the adsorbates.