Comparing the performance of density functionals in describing the adsorption of atoms and small molecules on Ni(111)

SURFACE SCIENCE

卷:700

Article

Goltl, Florian¹  Murray, Ellen A.¹  Tacey, Sean A.¹  Rangarajan, Srinivas^1,2  Mavrikakis, Manos¹ 

[1] Univ Wisconsin Madison, Dept Chem & Biol Engn, 1415 Engn Dr, Madison, WI 53706 USA

[2] Lehigh Univ, Dept Chem & Biol Engn, 111 Res Dr, Bethlehem, PA 18015 USA

关键词: Adsorption;    Density functional theory;    Dispersion corrections;    Error estimation;    Heat of adsorption;   

DOI  :  10.1016/j.susc.2020.121675

来源: Elsevier

【 摘 要 】

Reaction networks calculated using density functional theory (DFT) play a crucial role in understanding and predicting heterogeneous catalyst performance. However, results obtained using different density functionals can vary significantly. Accordingly, it is important to assess the accuracy of available functionals in capturing adsorption energetics derived from single-crystal adsorption microcalorimetry experiments. Here, we evaluate how different density functionals describe the molecular and dissociative adsorption of CH3I, the adsorption of CH3, I, and H, and the dissociative adsorption of CH4 on Ni(111). First, we identify energetically-preferred adsorbed states for each adsorbate at three surface coverages and calculate the corresponding enthalpies of adsorption at 160 K. Then, we compare the results to experimental measurements published in the literature. For each adsorption process we find at least one functional that is quantitatively accurate within experimental error, but no functional is accurate (within experimental error) for all adsorption processes studied. Even when assuming an additional DFT error of +/- 20 kJ/mol on top of the experimental error, only the PBE-D3 and RPBE-D3 functionals are accurate for all considered adsorption systems. These results indicate that quantitative agreement between density functional theory calculations and experimental measurements is both system-and functional dependent. Importantly, single-crystal adsorption microcalorimetry experiments will continue to play an important role for benchmarking density functionals.

【 授权许可】

Free