Consequences of Bond Forming

The external conditions determine the site-and-orientation specificity of the basic oxide tetrahedron, which generate versatile patterns of observation. The main identities of oxide surfaces are the following  

Because of oxygen penetrating into the top layer for tetrahedron formation, the first interlayer spacing expands. The production of metal ions in the second layer strengthens the interaction between the ionic second layer and the third metallic layer. Therefore, the spacing between the second and third atomic layer often contracts. 

The net gain in energy provides forces that drive reconstruction, though the orbit hybridization and the antibonding formation consume some amount of energy. Analysis of the Rh(001)-O clock reconstruction indicates that the driving force for the atomic dislocation also comes from other sources such as the alternative electrostatic repulsion and attraction along the (11) rhombi chain, and a response of bond tension that stabilizes the clock rotation. 

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