Zone center phonon frequencies in tetragonal zirconia: lattice dynamical study and new assignment proposition

A normal mode calculation of the zone center phonons in the tetragonal structure of ZrO2 compound has been performed with particular emphasis on the low frequency modes. A restricted set of stretching and bending force constants have been introduced and lead to a good agreement between theoretical and experimental Raman and IR phonon frequencies. The E-g symmetry of the two low frequency Raman modes which are involved in the softening process observed with increasing pressure were confirmed and none were left for a low frequency Al, totally symmetric mode as proposed in the literature. (C) 2001 Elsevier Science Ltd. All rights reserved.