Adsorption Site Preference Determined by Triangular Topology: Application of the Method of Moments to Transition Metal Surfaces

DOI HANDLE Web Site 被引用文献2件 参考文献103件 オープンアクセス

この論文をさがす

説明

The adsorption sites of the top and hollow on the close-packed surfaces of transition metals are well known. In this paper, which site is more preferred for the adsorption of atoms and molecular fragments on the metal surfaces is discussed based on the topology of the adsorption geometry. For this purpose, the method of moments for the electronic density of states is applied to the surface. Adsorption at the hollow site generates a triangular topology, leading to a more negative value of the third moment (μ_3) than that at the top site, which generates no triangular topology. When the difference in energy between the two adsorption sites is plotted against the band filling of the metal surface, a characteristic node at around the intermediate band filling can be found. This is a signature that the energy difference curve is controlled by μ_3. Roughly speaking, the hollow-site adsorption, which has a more negative μ_3 value, takes precedence at low band fillings, while the top site adsorption, which has a less negative μ_3 value, takes precedence at high band fillings. One can conclude that an adsorption structure with more three-membered rings on a surface is more stable at low electron counts whereas that with less three-membered rings is more stable at high electron counts. However, if the strength of the metal–adsorbate bond is significantly greater than that of the metal–metal bond, the effect of the second moment (μ_2) on the energy difference curve cannot be neglected. The hollow-site adsorption leads to a larger value of μ_2 due to the topological feature of a larger coordination number around the adsorbate atom. As a result, the hollow-site adsorption is preferred over the top site at any band filling.

収録刊行物

被引用文献 (2)*注記

もっと見る

参考文献 (103)*注記

もっと見る

関連プロジェクト

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ