Classification of processes in solids

Defect diffusion traditionally is treated as a process in continuum medium. However, discreteness of the crystalline lattice becomes important in particular situations, e.g., when defect recombination occurs in several hops (nearest neighbour recombination) [3, 4] or even for nearest-site hops of defects if their recombination is controlled by the tunnelling whose probability greatly changes on a scale of lattice constant [45, 46]. 

From pair kinetics toward the many-reactant problem 

In the last decades, both experimental data [2, 51] and theoretical studies [52-56] revealed the effect of the statistical similar defect aggregation under defect accumulation (permanent particle source). It means that the initial random mixture of defects of two kinds A and B during bimolecular reaction is 

This similar defect segregation arises due to the local fluctuations of particle defect) densities which is illustrated qualitatively in Fig. 3.8 production by a change of two or more similar defects (say. A) nearby creates a germ of their aggregate which increases in size with time since it is more stable and has a greater chance to survive than several isolated defects A the probability that the same number of defects B will be created statistically in the same 

---

Fig. 3.3. Schematic classification of processes in solid with defects, (a) Defect diffusion ...

---