Hollow site threefold coordinated

Fig. 5.1. Highly coordinated adatom sites at an fcc(lll) or an hcp(OOOl) surface. The upper picture shows a top view of the surface, labeling the two threefold coordinated hollow sites. The lower row illustrates the local geometries of the three high-symmetry interstitial sites between the first and second substrate layers. Metal atoms are depicted as light, large spheres, and oxygen atoms as dark, small spheres...

Fig. 2.1 Possible coordination environment for atomic chemisorption, a Atoms surrounding the fcc(OOl) fourfold (C4v) hollow site form an upside-down pyramid, b On the fcc(lll) and hcp(OOOl) surfaces, there are two types of threefold (Csv) hollow sites. Atoms surrounding the hcp(OOOl) hollow (7) form a tetrahedron. No atom exists in the substrate second layer below the fcc(lll) hollow site (II). c The fcc(llO) and its analog, d hcp(lOlO) surfaces possess alternate hcp(OOOl) (/) and fcc(lll) (II) facet sites along the close-packed direction (reprinted with permission from [3])...

Figure 9.22 Saturation of dangling bonds by adatoms, (a) Adatoms in a threefold symmetric hollow site, that is, H3 site, forming a (. 3 X. 3) reconstruction, (b) Adatoms in atop sites, that is, T4 site. The adatom and the second-layer atom below Interact weakly, which gives a nearly fourfold coordination that favors the T4 site In comparison to the...

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