Coadsorption of CO and H on Ni(110): evidence for a strong local COH interaction

doi:10.1016/0039-6028(92)90276-C

Surface Science

Volume 273, Issues 1–2, 15 June 1992, Pages 61-72

https://doi.org/10.1016/0039-6028(92)90276-C Get rights and content

Abstract

We have investigated differently prepared coadsorbate layers of H and CO on Ni(110) by thermal desorption, low-energy electron diffraction, ultraviolet photoemission and inverse photoemission. In addition we have carried out cluster calculations in order to model the electronic structure of the mixed COH layer on this surface and to investigate effects of H coadsorption on bond lengths and the corresponding stretching vibrations. We find evidence for a strong local COH interaction. No global H-induced effects, such as d-band filling, need to be invoked for the interpretation of the photoemission spectra. Moreover, neither changes in the long-range order of the coadsorbate layer nor a surface reconstruction seem to profoundly affect the character of the COH interaction. This supports the assumption of a local interaction mechanism.

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¹: Permanent address: Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1040 Sofia, Bulgaria.

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Coadsorption of CO and H on Ni(110): evidence for a strong local COH interaction

Abstract

Surf. Sci.

Surf. Sci.

J. Vac. Sci. Technol.

Surf. Sci.

Surf. Sci.

Surf. Sci.

Surf. Sci.

Surf. Sci.

J. Chem. Phys.

Surf. Sci.

Surf. Sci.

Surf. Sci.

Phys. Scr.

Phys. Rev. Lett.

Vacuum

Surf. Sci.

Surf. Sci.

Phys. Rev. B

Surf. Sci.

Surf. Sci.

Surf. Sci.