Structures with vacancy sublattices based on fcc and bcc packings of spheres and their stability at negative pressures

Abstract

Structures with regular sublattices of vacancies, vacancy clusters, and channels constructed from the fcc and bcc packings of spheres were analyzed. Homologous series of structures were constructed, and formulas were derived to correlate the basic structural characteristics with the composition of the “vacancy compounds” AmVn. The thermodynamic stabilities of structures with vacancies were compared with the stability of a flaw-free structure in the range of negative pressures using the simple interatomic interaction potential. Structures with vacancy clusters and channels may be more stable than the ideal structure in a certain range of pressures. This paper summarizes the results of simulations of structures with vacancy sublattices based on close packings of spheres described in this work and previous publications and their thermodynamic stability at negative pressures.