Jump to main content
Jump to site search

Issue 42, 2010
Previous Article Next Article

Stochastic approach to laser-induced ultrafast dynamics: the desorption of H2/D2 from Ru(0001)

Author affiliations

Abstract

The desorption of molecular hydrogen and deuterium induced by femtosecond-laser pulses is studied theoretically for the so-called DIMET (Desorption Induced by Multiple Electronic Transitions) process. These investigations are based on nonadiabatic classical Monte Carlo trajectory (CMCT) simulations on a ground and an excited state potential energy surface, including up to all six adsorbate degrees of freedom. The focus is on the hot-electron mediated energy transfer from the surface to the molecule and back, and the energy partitioning between the different degrees of freedom of the desorbing molecules. We first validate for a two-mode model comprising the desorption mode and the internal vibrational coordinate, the classical Monte Carlo trajectory method by comparing with Monte Carlo wavepacket (MCWP) calculations arising from a fully quantum mechanical open-system density matrix treatment. We then proceed by extending the CMCT calculations to include all six nuclear degrees of freedom of the desorbing molecule. This allows for a detailed comparison between theory and experiment concerning isotope effects, energy partitioning (translational, vibrational, and rotational energies and their distributions), and the dependence of these properties on the laser fluence. The most important findings are as follows. (i) CMCT agrees qualitative with the MCWP scheme. (ii) The basic experimental features such as the large isotope effect, the non-linear increase of yield with laser fluence, translationally hot products (in the order of several 1000 K) and non-equipartitioning of translational and internal energies (Etrans > Evib > Erot) are well reproduced. (iii) Predictions concerning a strong angular dependence of translational energies at large observation angles are also made.

Graphical abstract: Stochastic approach to laser-induced ultrafast dynamics: the desorption of H2/D2 from Ru(0001)

Back to tab navigation

Publication details

The article was received on 16 Jun 2010, accepted on 27 Aug 2010 and first published on 21 Sep 2010


Article type: Paper
DOI: 10.1039/C0CP00895H
Citation: Phys. Chem. Chem. Phys., 2010,12, 14082-14094
  •   Request permissions

    Stochastic approach to laser-induced ultrafast dynamics: the desorption of H2/D2 from Ru(0001)

    G. Füchsel, T. Klamroth, J. C. Tremblay and P. Saalfrank, Phys. Chem. Chem. Phys., 2010, 12, 14082
    DOI: 10.1039/C0CP00895H

Search articles by author

Spotlight

Advertisements