Mesoscopic clusters phenomena

Of special interest in the recent years was the kinetics of defect radiation-induced aggregation in a form of colloids-, in alkali halides MeX irradiated at high temperatures and high doses bubbles filled with X2 gas and metal particles with several nanometers in size were observed [58] more than once. Several theoretical formalisms were developed for describing this phenomenon, which could be classified as three general categories (i) macroscopic theory [59-62], which is based on the rate equations for macroscopic defect concentrations (ii) mesoscopic theory [63-65] operating with space-dependent local concentrations of point defects, and lastly (iii) discussed in Section 7.1 microscopic theory based on the hierarchy of equations for many-particle densities (in principle, it is infinite and contains complete information about all kinds of spatial correlation within different clusters of defects). 

Similar mesoscopic quantum effects take place also in short hydrogen-bonded chains and in small clusters, which include hydrogen bonds. The phenomenon of large proton polarizability and fast oscillations of the polarization of the chain were studied experimentally by Zundel and coworkers [6,249,288,289]. A theoretical study of macroscopic tunneling of the chain polarization has been conducted in Refs. 319-322. 

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