Changes in the potential energy upon the formation of vacancies in the volume and in the cores of crystallite-conjugation regions in cubic polycrystalline metals

Changes in the potential energy of atoms that constitute the nearest neighborhood of vacancies formed in the bulk of d transition and precious cubic metals have been determined. These changes agree with the available first-principles calculations of changes in the potential energy of atoms of the nearest neighborhood of vacancies. In the cores of crystallite-conjugation regions (CCRs) of bcc polycrystalline d transition metals, the formation of vacancies is accompanied by positive changes in the potential energy of atoms of their nearest neighborhood. The absolute magnitudes of these changes are several times less than the changes in the potential energy of atoms of the nearest neighborhood of vacancies in the bulk of these metals, in accordance with the relationship between the enthalpies of formation of vacancies in these regions of polycrystals. The changes in the potential energy of atoms of the nearest neighborhood of vacancies formed in the cores of CCRs of fcc polycrystalline metals are negative because of the split structure of vacancies in the CCR cores of such metals.