Nitrogen adsorption on Fe(111), (100), and (110) surfaces.

Nitrogen adsorption on Fe(111), (100), and (110) surfaces.
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by J.J.Mortensen, M. V. Ganduglia-Pirovano, L. B. Hansen, B. Hammer, P.
Stoltze, and J. K. Nørskov.

Surface Science, **422**, 8 (1999).

Abstract
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Adsorption energies and structures for N atoms on three low-index
surfaces of Fe have been calculated using density functional theory
(DFT) and the generalized gradient approximation (GGA). At low N
coverage the adsorption energy on Fe(100) is found to be ~0.7 eV higher
than on the (111) and (110) surfaces -- particularly the
c(2x2)-N/Fe(100) structure with the N atoms in four-fold sites is very
stable. We attribute the differences in adsorption energy to the lack of
four-fold sites on the (111) and (110) surfaces. We suggest that at
higher N coverages, islands with a structure similar to the
c(2x2)-N/Fe(100) structure will form on the (111) and (110) surfaces.