Atomic transport via point defects in crystals. IV. Anelastic relaxation

Abstract

The previously formulated kinetic theory of isothermal atomic transport via point defects is here applied to the description of anelastic relaxation in crystals containing defect pairs. Defect reactions leading to the dissociation and reformation of these pairs are included, but the symmetry and elastic strengths of the relaxation modes are unaffected, with the exception of modes having the full point-group symmetry of the crystal. In this respect anelastic relaxation is different from dielectric relaxation, the strength of which can be substantially affected by these reactions for reasons connected with the contributions which the dissociated defects make to the total measured electric current. The characteristic relaxation times associated with the elastically active modes are, however, shortened by these reactions.