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

Publication details

The article was received on 20 Jan 2010, accepted on 08 Apr 2010 and first published on 24 May 2010


Article type: Edge Article
DOI: 10.1039/C0SC00141D
Citation: Chem. Sci., 2010,1, 55-61
  •   Request permissions

    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

Search articles by author

Spotlight

Advertisements