Desorption of fragment ions from mono- and multilayered CCl 4 on Cu(100) by inner-shell photoexcitation
Abstract
Photon-stimulated desorption of fragment ions from mono- and multilayered CCl 4 on Cu(100) has been investigated using synchrotron radiation in the photon-energy range from 2810 to 2850 eV. For monolayer, only Cl + ions were desorbed. The desorption of the Cl + ions happens only at the Cl 1s→ σ* resonant excitation which mainly ends up in the v -4 σ* 1 state (v denotes the valence orbital). The result shows that the v -4 σ* 1 state survives even in the strong coupling system due to the fast bond-breaking process. In contrast, both the Cl + and CCl +3 ions were desorbed from multilayer where the coupling between adsorbate and substrate is weak. The desorption yield of the CCl +3 ions is almost proportional to the X-ray absorption yield regardless of the final electronic configuration. The desorption of the molecular fragment-ions is interpreted by the effect of Auger-stimulated secondary electrons due to the relatively slow movement of the heavy molecular species.
- Publication:
-
Surface Science
- Pub Date:
- May 1998
- DOI:
- 10.1016/S0039-6028(97)00936-9
- Bibcode:
- 1998SurSc.402..115B