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Early experimental data on void swelling in electron-irradiated materials disagree with the dislocation bias models based on the dislocation-point defect elastic interactions. Later, this became one of the factors that prompted the development of models based on production bias (PBM) as the main driver for swelling, which assumed that the dislocation bias was much lower than that predicted by theoretical analyses of dislocation bias. However, the PBM in its present form fails to account for important and common observations, namely, the indefinite void growth often observed under cascade irradiation and the swelling saturation observed under high-dose irradiation and in void lattices. In this paper, we show that these contradictions can be naturally resolved in the framework of the rate theory that accounts for the radiation-induced vacancy emission from extended defects, such as voids, dislocations and grain boundaries. This modification introduces a new bias type in the theory, namely, the emission bias. This modified rate theory agrees well with the experimental data and demonstrates that the original dislocation bias should be used in rate theory models along with the emission bias in different irradiation environments. The modified theory predictions include, but are not limited to, the radiation-induced annealing of voids, swelling saturation under high-dose irradiation, generally, and in void lattices, in particular. [ABSTRACT FROM AUTHOR]

Abstract: We propose a mechanism of void growth in di-atomic ionic crystals due to agglomeration of divacancies produced by interactions between dislocations and excitons. An exciton can cause movement of nearby dislocation jogs, resulting in the creation of equal numbers of anion and cation vacancies (Schottky defects). Owing to the heat generated locally during the exciton annihilation, the jog can be displaced while a divacancy arises in the lattice. Subsequent diffusion and agglomeration of divacancies can result in void formation and growth. We evaluate the void nucleation and growth rates in electron irradiated NaCl. [Copyright &y& Elsevier]

Abstract: Recent experimental and molecular dynamics results give evidence for the existence of the discrete solitons (DS’s), a.k.a. intrinsic localized modes (ILM’s), discrete breathers (DB’s) and quodons, which are stable, highly localized lattice excitations that can transfer energy along close-packed crystal directions. The DS interaction with crystal defects results in the amplification of the reaction rates, such as atom ejection and diffusion. In this paper, recent results on the DS detecting in three-dimensional crystal structures by means of molecular dynamics are discussed, and a new method of the rate theory modification in solids under irradiation is presented. [Copyright &y& Elsevier]