Abstract
Using time-resolved sum-frequency generation spectroscopy, the stretch vibration of carbon monoxide adsorbed on a single-crystal Ru(001) surface is investigated during femtosecond near-IR laser excitation leading to desorption. A large transient redshift, a broadening of the resonance, and a strong decrease in intensity are observed. These originate from coupling of the stretch to low-frequency modes, especially the frustrated rotation, that are highly excited in the desorption process.
- Received 9 December 1999
DOI:https://doi.org/10.1103/PhysRevLett.84.4653
©2000 American Physical Society