The parallel adsorption mechanism

The general results in Chap. 3 permit us to claim that critical effects can be interpreted qualitatively in terms of the ideal adsorbed layer model. Detailed mechanisms applied to interpret these phenomena must necessarily include a step of interaction between various intermediates (naturally, in the absence of the auto-catalytic steps). 

It is evident that such steps are not involved in linear mechanisms, including the two-step mechanism 

In kinetic models corresponding to schemes (2) and (3), the steady state is unique and stable. These mechanisms involve the participation of two intermediates. 

Let us consider a more complex case, i.e. mechanisms with three intermediates. 

The simplest detailed mechanism having a step of interaction between various intermediates includes three steps  

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