The dynamics of O atoms in a Ta-O solid solution were studied. The vibrational energies of interstitial O impurities were determined, and the metal-impurity interaction constants were calculated. The experimental data obtained suggested that an O atom was displaced from the center of the octahedral interstice of the crystal lattice. The O vibrational energy in Ta was shown to satisfy the relation between the local-mode energy and the transition metal-interstitial impurity distance that was common for all M-O systems.

Dynamics of Oxygen Atoms in the Ta-O Interstitial System. S.I.Morozov: Physics of the Solid State, 2006, 48[4], 615-21