Observation of a change of vibrational excitation mechanism with surface temperature: HCl collisions with Au(111).
نویسندگان
چکیده
We have measured the vibrational excitation probability (Pv) of HCl incident on a Au(111) surface at kinetic energies (Ei) of 0.59 eV to 1.37 eV and surface temperatures (Ts) of 273 K to 1073 K. For all energies, the slope of the Pv as a function of Ts exhibits a sharp increase above Ts approximately 800 K. We show this change in slope and the threshold behavior of Pv to be consistent with a change in excitation mechanism from an electronically adiabatic mechanical mechanism to an electronically nonadiabatic mechanism involving excited electron-hole pairs.
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ورودعنوان ژورنال:
- Physical review letters
دوره 98 23 شماره
صفحات -
تاریخ انتشار 2007