Probing structural changes upon carbon monoxide coordination to single metal adatoms

P. T. P. Ryan, M. Meier, Z. Jakub, J. Balajka, J. Hulva, D. J. Payne, T.-L. Lee, C. Franchini, F. Allegretti, G. S. Parkinson, D. A. Duncan

Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0QX, United Kingdom
Department of Materials, Imperial College London, London SW7 2AZ, United Kingdom
Institut für Angewandte Physik, TU Wien, 1040 Wien, Austria
University of Vienna, Faculty of Physics and Center for Computational Materials Science, 1090 Vienna, Austria
Physics Department E20, Technical University of Munich, 85748 Garching, Germany

J. Chem. Phys. 152 (2020) 051102

In this work, the adsorption height of Ag adatoms on the Fe₃O₄(001) surface after exposure to CO was determined using normal incidence x-ray standing waves. The Ag adatoms bound to CO (Ag₁^CO) are found to be pulled out of the surface to an adsorption height of 1.15 Å ± 0.08 Å, compared to the previously measured height of 0.96 Å ± 0.03 Å for bare Ag adatoms and clusters. Utilizing DFT+vdW+U calculations with the substrate unit cell dimension fixed to the experimental value, the predicted adsorption height for Ag₁^CO was 1.16 Å, in remarkably good agreement with the experimental results.

Corresponding author: Gareth S. Parkinson (parkinson).

You can download a PDF file of this open-access article from The Journal of Chemical Physics or from the IAP/TU Wien web server.