A First Principles Study of O-2/Ag(111) -Adsorption and Magnetic Properties-

作者：Kunisada Yuji^*; Nakanishi Hiroshi; Kasai Hideaki

来源：Journal of the Physical Society of Japan, 2011, 80(8): 084605.

DOI：10.1143/JPSJ.80.084605

• density functional theory
• oxygen adsorption
• molecular adsorption
• dissociative adsorption
• potential energy surface
• magnetic property
• metal surface

We have investigated the O-2 molecular and dissociative adsorption on Ag(111) surfaces. To clarify the adsorption properties, we performed first principles calculation based on spin-polarized density functional theory (DFT) with the generalized gradient approximation for the exchange-correlation energy. We calculated the potential energy surfaces (PES) for thirteen trajectories of O-2, which gives us information with respect to the relevant six dimensional PES. From these results, we found that the effective energy barrier of O-2 dissociative adsorption is about 1.24 eV. We also found that upon O-2 molecular and dissociative adsorption, the magnetic moments per O atom were 0.52 mu(B) and 0.32 mu(B), respectively. For reference, the isolated O-2 and Ag(111) surfaces have the magnetic moments of 2.0 mu(B) and 0.0 mu(B). In O-2 dissociative adsorption, ferromagnetic behaviors were induced by ferromagnetic direct exchange interactions and superexchange interactions. Superlattice structures of O atoms which have an effective ferromagnetic superexchange interaction made ferromagnetic states feasible.

• 出版日期2011-8