RuO2 surface, structural models

Figure 8. a) Schematic view of the surface structure of an ideal RuOid 10) singlecrystal, where solid circles represent Ru atoms in the surface plane, open circles O atoms in the surface plane, and dotted open circles O atoms below surface plane b) model of an ideal RuO2(110) single-crystal. Ihe RuO2(110) surface contains two kinds of coordinatively unsaturated (CUS) atoms two-fold bridging O (Obr) and five-fold Ru (Rucus)- The Ojf is the O atoms that lay in the plane in the Ru atoms and posses its bulk-like three-fold coordination. 

Fig. 1.22 Derived structural models of the RuO2(110) surface at the potentials corresponding to the data shown in Fig. 1.21 b. The black balls represent the Ru atoms. The grey balls represent oxygen atoms in the bulk, on the surface bonded to Ru, and in the water molecules, respectively.

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