CO adsorption on metal surfaces: a hybrid functional study with plane wave basis set

TL;DR

This study compares different density functional theory methods to accurately predict CO adsorption sites on metal surfaces, highlighting the improved performance of hybrid functionals over traditional approaches.

Contribution

It demonstrates that hybrid functionals like PBE0 and HSE03 better predict CO adsorption sites on Cu and Rh surfaces, addressing limitations of LDA and GGA functionals.

Findings

Hybrid functionals correct site preference predictions for Cu and Rh.

LDA and GGA favor hollow sites contrary to experiments.

Hybrid functionals still fail for Pt but reduce hollow site stabilization.

Abstract

We present a detailed study of the adsorption of CO on Cu, Rh, and Pt (111) surfaces in top and hollow sites. The study has been performed using the local density approximation, the gradient corrected functional PBE, and the hybrid Hartree-Fock density functionals PBE0 and HSE03 within the framework of generalized Kohn-Sham density functional theory using a plane-wave basis set. As expected, the LDA and GGA functionals show a tendency to favor the hollow sites, at variance with experimental findings that give the top site as the most stable adsorption site. The PBE0 and HSE03 functionals reduce this tendency. In fact, they predict the correct adsorption site for Cu and Rh but fail for Pt. But even in this case, the hybrid functional destabilizes the hollow site by 50 meV compared to the PBE functional. The results of the total energy calculations are presented along with an analysis of the projected density of states.