Platinum-iodine monolayers

At higher surface coverages (more than Vi but less than 1), anions can be entirely displaced by copper adatoms from the surface or both form a two-layer structure in which anions are adsorbed on both the platinum and the copper sites. The final step is the total filling of the copper monolayer to form a bilayer phase with a disordered anion ad-layer on the topmost of Cu-Pt(lll) [106] or an ordered (2 x 2) bilayer of copper-halide structure on Pt(100) [104], The same physical models can be used in the case of bromide and chloride with little differences between the anion distances with a surface structure like that of a honeycomb ad-layer. The situation accounting for iodine adsorption is very different because of its large atomic radius and specific adsorption on noble metals. 

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