The quantum dynamics of H2 on Cu(111) at a surface temperature of 925 K: Comparing state-of-the-art theory to state-of-the-art experiments 2

** Authors:

B. Smits
M. F. Somers

** Contact e-mail:

b.smits@lic.leidenuniv.nl
m.somers@chem.leidenuniv.nl

** Abstract:

State-of-the-art 6D quantum dynamics simulations for the dissociative chemisorption of H$_{2}$ on a thermally distorted Cu(111) surface, using the static corrugation model, were analysed to produce several (experimentally available) observables.
The expected error, especially important for lower reaction probabilities, was quantified using wavepackets on several different grids as well as two different analysis approaches to obtain more accurate results in the region where a slow reaction channel was experimentally shown to be dominant.
Lowest reaction barrier sites for different thermally distorted surface slabs are shown to not just be energetically, but also geometrically, different between surface configurations, which can be used to explain several dynamical effects found when including surface temperature effects.
Direct comparison of simulated time-of-flight spectra to those obtained from state-of-the-art desorption experiments showed much improved agreement compared to the perfect lattice BOSS approach.
Agreement with experimental rotational and vibrational efficacies also somewhat improved when thermally excited surfaces were included in the theoretical model.
Finally, we present clear quantum effects in the rotational quadrupole alignment parameters found for the lower rotationally excited states, which underlines the importance of careful quantum dynamical analyses of this system.

** Folder FIG1:

Datafiles used in the figure, included are the BOSS results obtained for different time steps.
QCD datafiles also contain scattering to every rovib state, as well as total trajectories, total weight (relevant for binning methods) etc.


** Folder FIG23:

Data for contour plot in r, Z, E format. Units in Angstrom and eV.


** Folder FIG4:

Datafiles used in the figure, included are the BOSS and EAM-SCM results obtained.
Experimental curves simulated from the ERF parameters published by Kaufmann et al. are also included.


** Folder FIG5:

Fitting parameters for ERF fits of EAM-SCM and BOSS results.
Experimental results are not included, these can be found in the work of Kaufmann et al. (JCP 148, 194703 (2018).)
ChiSq is also included as an indication of the goodness of the fit.


** Folder FIG67_Tab1:

Threshold offsets, and rotational and vibrational efficacies for BOSS and EAM-SCM results.
Included are the results of the offsets obtained using fits to the FPC functional form, although all fitted curves gave (close to) equal results.
For vibrational efficacies the J=0 results were used in the final paper.
Again ChiSq is included to give an indication of the goodness of the dS fit.


** Folder FIG8:

Data used in the figure, for both BOSS and EAM-SCM at QD and QCD level.
Also included in the files is state-specific scattering, and weights and total trajectories for the QCD results.