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Polarization-Dependent Resonant Anomalous Surface X-ray Scattering of CO/Pt(111)

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 نشر من قبل Hoydoo You
 تاريخ النشر 2005
  مجال البحث فيزياء
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Polarization dependence of resonant anomalous surface x-ray scattering (RASXS) was studied for interfaces buried in electrolytes or in high-pressure gas. We demonstrate that RASXS exhibits strong polarization dependence when the surface is only slightly modified by adsorption of light elements such as carbon monoxide on platinum surfaces. s- and p-polarization RASXS data were simulated with the latest version of ab initio multiple scattering calculations (FEFF8.2). Elementary considerations are additionally presented for the origin of the polarization dependence in RASXS.


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Resonance anomalous surface x-ray scattering (RASXS) technique was applied to electrochemical interface studies. It was used to determine the chemical states of electrochemically formed anodic oxide monolayers on platinum surface. It is shown that RA SXS exhibits strong polarization dependence when the surface is significantly modified. The polarization dependence is demonstrated for three examples; anodic oxide formation, sulfate adsorption, and CO adsorption on platinum surfaces. s- and p- polarization RASXS data were simulated with the latest version of ab initio multiple scattering calculations (FEFF8.2). Elementary theoretical considerations are also presented for the origin of the polarization dependence in RASXS.
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