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Metastable precursors during the oxidation of the Ru(0001) surface

Karsten Reuter·M. Veronica Ganduglia-Pirovano·Catherine Stampfl·Matthias Scheffler
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Abstract

Using density-functional theory, we predict that the oxidation of the Ru(0001) surface proceeds via the accumulation of sub-surface oxygen in two-dimensional islands between the first and second substrate layer. This leads locally to a decoupling of an O-Ru-O trilayer from the underlying metal. Continued oxidation results in the formation and stacking of more of these trilayers, which unfold into the RuO_2(110) rutile structure once a critical film thickness is exceeded. Along this oxidation pathway, we identify various metastable configurations. These are found to be rather close in energy, indicating a likely lively dynamics between them at elevated temperatures, which will affect the surface chemical and mechanical properties of the material.

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Karsten Reuter, M. Veronica Ganduglia-Pirovano, Catherine Stampfl, Matthias Scheffler. 2001-09-26. Metastable precursors during the oxidation of the Ru(0001) surface. https://doi.org/10.1103/physrevb.65.165403

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