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The Adsorption of Atomic Nitrogen on Ru(0001): Geometry and Energetics

S. Schwegmann·A. P. Seitsonen·H. Dietrich·H. Bludau·H. Over·K. Jacobi·G. Ertl
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Abstract

The local adsorption geometries of the (2x2)-N and the (sqrt(3)x sqrt(3))R30^o -N phases on the Ru(0001) surface are determined by analyzing low-energy electron diffraction (LEED) intensity data. For both phases, nitrogen occupies the threefold hcp site. The nitrogen sinks deeply into the top Ru layer resulting in a N-Ru interlayer distance of 1.05 AA and 1.10 AA in the (2x2) and the (sqrt(3)x sqrt(3))R30^o unit cell, respectively. This result is attributed to a strong N binding to the Ru surface (Ru--N bond length = 1.93 AA) in both phases as also evidenced by ab-initio calculations which revealed binding energies of 5.82 eV and 5.59 eV, respectively.

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S. Schwegmann, A. P. Seitsonen, H. Dietrich, H. Bludau, H. Over, K. Jacobi, G. Ertl. 1997-03-04. The Adsorption of Atomic Nitrogen on Ru(0001): Geometry and Energetics. https://doi.org/10.1016/s0009-2614(96)01394-2

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