Single crystals of yttria-stabilized zirconia (12 mol % of ${\mathrm{Y}}_2$${\mathrm{O}}_3$) have been x-ray irradiated at room temperature. The electron paramagnetic resonance spectrum of the filled electron traps is analyzed in terms of a single oxygen vacancy type of defect with its symmetry axis along the 〈111〉 direction. The angular dependence of the linewidth and the asymmetry of the line shape are attributed to the disordered rearrangements of the anion sublattice surrounding the oxygen vacancy. This affects the local crystal fields and the directions of the symmetry axis of the defects.

• Received 20 March 1989

DOI:https://doi.org/10.1103/PhysRevB.40.6518