Adsorption of SO2 on Pd(100) Studied by S K-Edge XAFS
نویسندگان
چکیده
Surface structure and an electronic property of SO2 adsorbed on Pd(100) were studied by S K-edge NEXAFS, SEXAFS and Sls XPS. The molecule was found by the polar-angle dependent NEXAFS to adsorb with the molecular plane normal to the Pd(100) surface. This is a clear contrast to the S02/Ni(100) case where the molecule lies flat on the surface. From the peak position of XPS and the x* peak height of the N E W S spectra, we can deduce that the amount of the charge transfer Gom Pd to SO2 is smaller than that from Ni. The SEXAFS analysis indicates that the S atom of the molecule is located at the bridge site and that one 0 atom also directly interacts with the metal surface. The difference of the adsorbate structure between S02Pd and S02/Ni can be explained in terms of chemical bonding between the substrate and SO?.
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