Abstract
Exploring the role of van der Waals (vdW) forces on the adsorption of molecules on extended metal surfaces has become possible in recent years thanks to exciting developments in density functional theory (DFT). Among these newly developed vdW-inclusive methods, interatomic vdW approaches that account for the nonlocal screening within the bulk [V. G. Ruiz, W. Liu, E. Zojer, M. Scheffler, and A. Tkatchenko, Phys. Rev. Lett. 108, 146103 (2012)] and improved nonlocal functionals [J. Klimeš, D. R. Bowler, and A. Michaelides, J. Phys.: Condens. Matter 22, 022201 (2010)] have emerged as promising candidates to account efficiently and accurately for the lack of long-range vdW forces in most popular DFT exchange-correlation functionals. Here we have used these two approaches to compute benzene adsorption on a range of close-packed (111) surfaces upon which it either physisorbs (Cu, Ag, and Au) or chemisorbs (Rh, Pd, Ir, and Pt). We have thoroughly compared the performance between the two classes of vdW-inclusive methods and when available compared the results obtained with experimental data. By examining the computed adsorption energies, equilibrium distances, and binding curves we conclude that both methods allow for an accurate treatment of adsorption at equilibrium adsorbate-substrate distances. To this end, explicit inclusion of electrodynamic screening in the interatomic vdW scheme and optimized exchange functionals in the case of nonlocal vdW density functionals is mandatory. Nevertheless, some discrepancies are found between these two classes of methods at large adsorbate-substrate separations.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.