[20a-E319-1~7] 6.5 Surface Physics, Vacuum

[20a-E319-1] [Young Scientist Presentation Award Speech] Extent of spin contamination and static correlation errors in DFT/plan-wave calculation of surfaces

〇Kohei Tada¹, Tomohiro Maruyama², Hiroaki Koga³, Mitsutaka Okumura^2,3, Shingo Tanaka¹ (1.AIST, 2.Osaka Univ., 3.ESICB)

Keywords:density functional theory, Spin contamination error, interaction between molecule and surface

The presented study established an estimation scheme of spin contamination error on density functional theory calculations for surface reactions (AP-DFT/plane-wave scheme), and the effect was clarified. For a case of Au atoms diffusion and aggregation on a MgO (001) surface, the AP-DFT/plane-wave scheme clarified that the spin contamination and static correlation errors affect the potential energy curve. In addition, comparing with the results of Au atoms aggregation in gas-phase, it was shown that (1) the maximum value of the spin contamination error in surface reactions is smaller than that in gas-phase reactions, whereas the area causing spin contamination in the surface reaction is wider than that in the gas-phase reaction, and (2) the effects of spin contamination and static correlation emerge when the dissociating adsorbate/surface interaction becomes larger than the covalent interaction in the adsorbate.