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Title: Dissociation and recombination of D{sub 2} on Cu(111): Ab initio molecular dynamics calculations and improved analysis of desorption experiments

Obtaining quantitative agreement between theory and experiment for dissociative adsorption of hydrogen on and associative desorption of hydrogen from Cu(111) remains challenging. Particularly troubling is the fact that theory gives values for the high energy limit to the dissociative adsorption probability that is as much as two times larger than experiment. In the present work we approach this discrepancy in three ways. First, we carry out a new analysis of the raw experimental data for D{sub 2} associatively desorbing from Cu(111). We also perform new ab initio molecular dynamics (AIMD) calculations that include effects of surface atom motion. Finally, we simulate time-of-flight (TOF) spectra from the theoretical reaction probability curves and we directly compare them to the raw experimental data. The results show that the use of more flexible functional forms for fitting the raw TOF spectra gives fits that are in slightly better agreement with the raw data and in considerably better agreement with theory, even though the theoretical reaction probabilities still achieve higher values at high energies. The mean absolute error (MAE) for the energy E{sub 0} at which the reaction probability equals half the experimental saturation value is now lower than 1 kcal/mol, the limit that definesmore » chemical accuracy, while a MAE of 1.5 kcal/mol was previously obtained. The new AIMD results are only slightly different from the previous static surface results and in slightly better agreement with experiment.« less
Authors:
; ; ;  [1] ; ;  [2] ;  [1] ;  [3]
  1. Leiden Institute of Chemistry, Leiden University, Gorlaeus Laboratories, P.O. Box 9502, 2300 RA Leiden (Netherlands)
  2. Departamento de Química Módulo 13, Universitad Autónoma de Madrid, 28049 Madrid (Spain)
  3. (Germany)
Publication Date:
OSTI Identifier:
22308243
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 12; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ACCURACY; ADSORPTION; ATOMS; DESORPTION; DISSOCIATION; HYDROGEN; MOLECULAR DYNAMICS METHOD; PROBABILITY; RECOMBINATION; SPECTRA