Local structure of CO coadsorbed with O on Ni(111): A temperature-dependent study
Por:
Kang J.-H., Toomes R.L., Robinson J., Woodruff D.P., Terborg R., Polcik M., Hoeft J.T., Baumgärtel P., Bradshaw A.M.
Publicada:
1 ene 2001
Resumen:
Using C 1s scanned-energy mode photoelectron diffraction (PhD), the local geometry of CO adsorbed onto a Ni(111)(2 × 2)-O surface has been investigated as a function of the temperature of dosing or subsequent annealing. Around room temperature the CO adopts local atop sites in agreement with the previous interpretation of vibrational spectroscopy, but at low temperature a substantial fraction of the CO molecules adopt the hollow sites occupied in the absence of the preadsorbed O, generally consistent with the results of an earlier PhD study. Heating such a surface leads to a new state in which only atop sites are occupied, but this appears to be a result of desorption of the hollow species rather than any transformation of sites. The results confirm the qualitative site occupations deduced in a recent study of this system which used C 1s and O 1s photoelectron binding energy shifts to fingerprint the local site changes.
Filiaciones:
Kang J.-H.:
Physics Department, University of Warwick, Coventry CV4 7AL, United Kingdom
Toomes R.L.:
Physics Department, University of Warwick, Coventry CV4 7AL, United Kingdom
Robinson J.:
Physics Department, University of Warwick, Coventry CV4 7AL, United Kingdom
Woodruff D.P.:
Physics Department, University of Warwick, Coventry CV4 7AL, United Kingdom
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
Terborg R.:
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
Polcik M.:
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
Hoeft J.T.:
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
Baumgärtel P.:
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
Bradshaw A.M.:
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
Max-Planck-Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
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