Abstract
Past efforts to achieve selective bond scission by vibrational excitation have been thwarted by energy thermalization. Here we report resonant photodesorption of hydrogen from a Si(111) surface using tunable infrared radiation. The wavelength dependence of the desorption yield peaks at 0.26 electron volt: the energy of the Si-H vibrational stretch mode. The desorption yield is quadratic in the infrared intensity. A strong H/D isotope effect rules out thermal desorption mechanisms, and electronic effects are not applicable in this low-energy regime. A molecular mechanism accounting for the desorption event remains elusive.
Original language | English (US) |
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Pages (from-to) | 1024-1026 |
Number of pages | 3 |
Journal | Science |
Volume | 312 |
Issue number | 5776 |
DOIs | |
State | Published - May 19 2006 |