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Structure and stability of a high-coverage (1x1) oxygen phase on Ru(0001)

C. Stampfl·S. Schwegmann·H. Over·M. Scheffler·G. Ertl
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Abstract

The formation of chemisorbed O-phases on Ru(0001) by exposure to O_2 at low pressures is apparently limited to coverages Theta <= 0.5. Using low-energy electron diffraction and density functional theory we show that this restriction is caused by kinetic hindering and that a dense O overlayer (Theta = 1) can be formed with a (1x1) periodicity. The structural and energetic properties of this new adsorbate phase are analyzed and discussed in view of attempts to bridge the so-called "pressure gap" in heterogeneous catalysis. It is argued that the identified system actuates the unusually high rate of oxidizing reactions at Ru surfaces under high oxygen pressure conditions.

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C. Stampfl, S. Schwegmann, H. Over, M. Scheffler, G. Ertl. 1996-07-30. Structure and stability of a high-coverage (1x1) oxygen phase on Ru(0001). https://doi.org/10.1103/physrevlett.77.3371

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