Berlin 2005 – wissenschaftliches Programm

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O: Oberflächenphysik

O 46: Adsorption an Oberfl
ächen V

O 46.10: Vortrag

Dienstag, 8. März 2005, 18:00–18:15, TU EB420

Accurate prediction of the CO adsorption site on Cu(111) from first-principles calculations — •Qing-Miao Hu, Karsten Reuter, and Matthias Scheffler — Fritz-Haber-Institut, Faradayweg 4-6, D-14195 Berlin

It is well known that density-functional theory (DFT) with present-day jellium-based local or gradient-corrected exchange-correlation (xc) functionals fails to predict the correct adsorption site of CO on most close-packed metal surfaces, including Pt(111) and Cu(111). Motivated by earlier findings, e.g. [1], that showed that the error of these functionals is “nearsighted”, we present here a systematic study of the correction of the xc energy for CO adsorption. The clue is to use appropriate energy differences and appropriately chosen clusters around the adsorption site. Again [1] we find that the xc correction (not the total energy) converges rapidly with cluster size. Calculations using DFT-LDA, PBE, and B3LYP as well as HF+MP2 are presented.

For the example of low-coverage adsorption of CO at Cu(111) we therewith indeed obtain the correct on-top adsorption site. We also explain our results, as well as the failure of standard DFT calculations in a simple physical picture.

[1] C. Filippi, S.B. Healy, P. Kratzer, E. Pehlke, and M. Scheffler, Phys. Rev. Lett. 89, 166102 (2002)