An elastic attraction of dissimilar particles

As it was mentioned above, up to now only the dynamic interaction of dissimilar particles was treated regularly in terms of the standard approach of the chemical kinetics. However, our generalized approach discussed above allow us for the first time to compare effects of dynamic interactions between similar and dissimilar particles. Let us assume that particles A and B attract each other according to the law (7ab( ) = — Ar, which is characterized by the elastic reaction radius = (/3A) /. The attraction potential for BB pairs is the same at r ro but as earlier it is cut-off, as r ro. Finally, pairs AA do not interact dynamically. Let us consider now again the symmetric and asymmetric cases. In the standard approach the relative diffusion coefficient Dp,/D and the potential (7bb( ) do not affect the reaction kinetics besides at long times the reaction rate tends to the steady-state value of K(oo) oc rg. 

The results of the incorporation of AB attraction into the kinetic equations are plotted in Figs 6.36 to 6.38. The decay of the defect concentration shown 

As earlier for the case Uab = 0 (Fig. 6.35), the correlation functions X r,t) and Y r,t) shown in Fig. 6.38 (a) and (b) demonstrate appearance of the domain structure in a reaction volume with interacting particles, having the distinctive size = /Df. Interaction within AB pairs holds at the relative distances r (at long times re C takes place) and only slightly modifies the AB pair distribution on the domain boundaries, where the reaction takes place, but do not influence essentially the entire mechanism of the domain formation (the effect of statistical aggregation). 

In conclusion of Section 6.3 we wish to stress that the elastic attraction of similar defects (reactants) leads to their dynamic aggregation which, in turn, reduces considerably the reaction rate. This effect is mostly pronounced for the intermediate times (dependent on the initial defect concentration and spatial distribution), when the effective radius of the interaction exceeds greatly the diffusion length = V. In this case the reaction kinetics is governed by the elastic interaction of both similar and dissimilar particles. A comparative study shows that for equal elastic constants A the elastic attraction of similar particles has greater impact on the kinetics than interaction of dissimilar particles. 

At longer times, when the effect of the statistical aggregation 

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