The changes in the potential (ucmpl) and vibrational (ɛcmpl) energies and the signs of changes in the interatomic spacings (Δacmpl) upon the formation of vacancies in oxygen-alloyed cores of crystallite-conjugation regions in polycrystalline 4d and 5d transition metals Mo, Ta, and W were determined. The potential energy upon the formation of vacancies (upon the formation of vacancy complexes with oxygen atoms—vacO complexes) in the oxygen-alloyed cores of crystallite-conjugation regions in polycrystalline Mo, Ta, and W increased (ucmpl were positive), as upon the formation of vacancies in pure crystallite-conjugation region cores of transition body-centred cubic d metals. The vibrational energy upon the formation of vacancies in oxygen-alloyed crystallite-conjugation region cores in polycrystalline Mo, Ta and W decreased (ɛvacO were negative). The negative sign of changes in the vibrational energy upon the formation of vacancies in the oxygen-alloyed crystallite-conjugation region cores in Mo, Ta, and W (ɛvacO < 0) agreed with the independent determinations of the sign of changes in the vibrational energy in the oxygen-alloyed crystallite-conjugation region cores in polycrystalline tungsten (ɛvacO)W using Mössbauer measurements of the Debye temperature. The signs of changes in the interatomic spacings upon the formation of vacancies in the oxygen-alloyed crystallite-conjugation region cores in polycrystals of Mo, Ta and W were negative (ΔaVacO < 0), in contrast to positive (0 < Δa BCC) changes in the interatomic distances in the nearest neighbourhood of vacancies formed in pure crystallite-conjugation region cores in Mo, Ta and W.

Changes in the Potential and Vibrational Energies upon the Formation of Vacancies in Oxygen-Doped Cores of Crystallite-Conjugation Regions of Polycrystalline 4d and 5d BCC Transition Metals. S.M.Klotsman, A.N.Timofeev: The Physics of Metals and Metallography, 2008, 105[3], 305-12