Jump to main content
Jump to site search

Issue 1, 2010
Previous Article Next Article

Vibrational overtone excitation in electron mediated energy transfer at metal surfaces

Author affiliations

Abstract

Vibrational overtone excitation is, in general, inefficiently stimulated by photons, but can under some circumstances be efficiently stimulated by electrons. Here, we demonstrate electron mediated vibrational overtone excitation in molecular collisions with a metal surface. Specifically, we report absolute vibrational excitation probabilities to ν = 1 and 2 for collisions of NO(ν = 0) with a Au(111) surface as a function of surface temperature from 300 to 985 K. In all cases, the observed populations of vibrationally excited NO are near those expected for complete thermalization with the surface, despite the fact that the scattering occurs through a direct “single bounce” mechanism of sub-ps duration. We present a state-to-state kinetic model, which accurately describes the case of near complete thermalization (a regime we call the strong coupling case) and use this model to extract state-to-state rate constants. This analysis unambiguously shows that direct vibrational overtone excitation dominates the production of ν = 2 and that, within the context of our model, the intrinsic strength of the overtone transition is of the same order as the single quantum transition, suggesting a possible way to circumvent optical selection rules in vibrational pumping of molecules. This result also suggests that previous measurements of vibrational relaxation of highly vibrationally excited NO exhibiting highly efficient multi-quantum jumps (Δν ∼ −8) are mechanistically similar to vibrational excitation of NO(ν = 0).

Graphical abstract: Vibrational overtone excitation in electron mediated energy transfer at metal surfaces

Back to tab navigation

Supplementary files

Article information


Submitted
20 Jan 2010
Accepted
08 Apr 2010
First published
24 May 2010

Chem. Sci., 2010,1, 55-61
Article type
Edge Article

Vibrational overtone excitation in electron mediated energy transfer at metal surfaces

R. Cooper, I. Rahinov, Z. Li, D. Matsiev, D. J. Auerbach and A. M. Wodtke, Chem. Sci., 2010, 1, 55
DOI: 10.1039/C0SC00141D

Social activity

Search articles by author

Spotlight

Advertisements