Temperature dependence of a period of the modulated structure in atom-vacancy solid solution

Abstract

The effective vacancy–vacancy interaction is considered. Based on the continuum approximation for the Fourier components of strain-induced vacancy–vacancy interaction energies, approximating expressions for their expansion coefficients are obtained depending on the elasticity moduli, longitudinal and transverse phonon frequencies, and vacancy-concentration-dependent lattice parameter. The behaviour of k-dependent Fourier components of the strain-induced vacancy–vacancy interaction energies near the Brillouin zone centre, A(n)+B(n)k2, is analysed. As shown, A(n) < 0 and B(n) > 0 along all the high-symmetry [100], [110], [111], [½10] directions in reciprocal space for f.c.c. crystals with negative anisotropy factor. The criterion of modulated-structure formation for interacting vacancies in f.c.c. crystals is considered. Dependence of the modulatedstructure period on temperature is plotted. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/20841