Formulation Bond and Atomic Valence

In order to examine the effects of electronegativity and the scale of the lattice constant on the observations, one may compare the patterns of reconstruction of the 0-(Rh, Pd)(110) surfaces with those of the 0-Cu(l 10) surface. 

It is easy to understand that, reacting with the more open (Pd, Rh)(II0) surfaces, oxygen adsorbates move from the C2v hollow sites to the tilted threefold fcc(l 1 l)-facet sites rather than the hcp(OOOl) facet sites of the fcc(llO) surface (Fig. 2.1). Bonding to two atoms in the second layer will create the same pattern of 

In the precursor phase, or at very low oxygen coverage, oxygen deposits randomly into the Ctv hollow site to form a B5O cluster. This cluster can be expressed as  

B5O forms by bonding to the B atom underneath and the 0 polarizes its four surface neighbors. 

At 0o = 1/3 ML, develops and the (2 x 3)-20 unit cell forms. The (2 X 3) unit cell contains two quasi-tetrahedron, which can be expressed as  

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