Self exchange silver

Silver porphyrins are interesting because of the existence of disilver(I), paramagnetic silver(II), and diamagnetic silver(III) complexes which has been known for a long time [7, 8]. The latter are favorably prepared by electrochemical [299] or peroxodisulfate [300-302] oxidation of silver(II) porphyrins. The Ag(III) porphyrins were used for and 2H resonance experiments [299] on one hand and for the determination of monomer-dimer equilibria [301] or self-exchange rate constants [301] at water-soluble silver porphyrins. 

We have labeled all possible processes by a binary notation that is explained in Figure 3.2. According to Muller and Ibach [12], the exchange mechanism, in which an atom leaves the terrace and is simultaneously replaced by an adatom, is unfavorable on Ag(lOO) and was therefore not considered for silver, but this process was implemented later for the self-diffusion of Au on Au(lOO) for more details, see Section 3.6. 

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