Particle energy, interaction probability

Obviously, both the energy profile of type I and the PS model should be treated as an idealization of any real situation because, at very small separations, the interaction energy must become positive due to the Bom repulsion preventing particle-wall penetration. In the DLVO theory, these repulsive interactions were not considered. Even at the present time, no quantitative theory of these interactions for macroscopic objects have been developed. Assuming that the repulsive part of the potential is described for atoms and molecules by the 6-12 power law, one may expect that for the particle-wall interactions, r These interactions seem, therefore, very short ranged, probably not exceeding 0.5-1 nm. 

Let us thus consider a model in which the association energy depth changes when two reacting particles are approaching the surface see Refs. 86,90. If in the vicinity of the surface the binding energy is lower than it is far from the surface, the probability of the chemical reaction to occur in the surface zone decreases. Similarly to the previous case, we consider an equimolar mixture of associating hard spheres of equal diameters. The interaction between the species a and (3 is assumed in the form... 

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