Nonanalytic Character of the Law of Dispersion of Interaction Between Point Defects in Crystals

摘要

With the assumption that indirect indirect interaction between point defects (d) is conditioned by distortions induced by them in a crystal (Me) and can be studied within the quasi-harmonic approximation by the lattice-statics method (in a general case taking into consideration a noncentral character of ('pairwise') 'interparticle' d-Me interaction), and the energy parameters of 'direct' d-d interaction may be estimated satisfactorily by means of simple semiempirical approximations, some causes of salient features are analysed (in particular, gaps of dispersion curves and saltuses of their slopes) for total interaction between such defects (site vacancies, substitutional and interstitial impurity atoms) within f.c.c., b.c.c. or h.c.p. metal Me taking into account its discrete structure (atomism), elasticity anisotropy, and also 'size' effect. The inapplicability is illustrated of long-wavelength (and, in particular, continuum) approximation for the description of a number of the phenomena (such as spinodal decomposition etc.) in interstitial solutions based on f.c.c., b.c.c., and h.c.p. metals, and also in substitutional solutions based on f.c.c. and h.c.p. metals.