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).
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by B. Hammer.

Phys. Rev. B, **63**, 205423 (2001).

Abstract
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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.