Abstract
Previous measurements of vibrational relaxation lifetimes for molecules adsorbed at metal surfaces yielded values of 1–3 ps; however, only chemisorbed molecules have been studied. We report the first measurements of the vibrational relaxation lifetime of a molecule physisorbed to a metal surface. For adsorbed on Au(111) at 35 K the vibrational lifetime of the excited stretching mode is . The long lifetime seen here is likely to be a general feature of physisorption, which involves weaker electronic coupling between the adsorbate and the solid due to bonding at larger distances.
- Received 8 March 2019
DOI:https://doi.org/10.1103/PhysRevLett.123.156101
© 2019 American Physical Society