First-Principles Determination of the Soft Mode in Cubic ZrO₂


K Parlinski, ZQ Li, Yoshiyuki Kawazoe

Physical Review Letters 78(21), 4063-4066 (1997)

A direct approach to calculate the phonon dispersion using an ab initio force constant method is introduced. The phonon dispersion and structural instability of cubic ZrO₂ are found using a supercell method in the local-density approximation. The force constants are determined from the Hellmann- Feynman forces induced by the displacement of an atom in the 2×2×2 fcc supercell. This size of the supercell gives “exact” phonon frequencies at Γ, X, L, W Brillouin zone points. The phonon dispersion curves show a pronounced soft mode at the X point, in agreement with the experimentally observed cubic to tetragonal phase transition.

  • linkedin3
  • Twitter Social Icon
  • YouTube Social  Icon
  • Facebook Social Icon
  • Researchgate

© 2020 by Materials Design, Inc. 

Privacy Policy
Materials Design® and MedeA® are registered trademarks of Materials Design, Inc.