Raman Scattering Study of the Crystallization and Phase Transformations of ZrO ₂

X‐ray diffraction, electron diffraction, and Raman scattering measurements are presented for dehydrated amorphous ZrO 2 . Although the material lacks sufficient crystallinity to diffract X rays, electron diffraction patterns indicate a microcrystallinity with a grain size of 15 to 30 A. Raman spectra characteristic of the metastable tetragonal polymorph were obtained from these materials. Heating the amorphous materials induces recrystallization into first a metastable tetragonal phase and then the stable monoclinic phase.