fig2

Figure 2. (A) Crystal structure projections of five HfO₂ phases along the four major zone axes; (B) HAADF-STEM images of four different grains (from the perspective zone axes); (C) STEM image of Gd:HfO₂ film; (D) PACBED pattern. Simulated PACBED patterns for the (E) Pca2₁, (F) Pbca, and (G) Pbcm phases^[22]. Reprinted from Ref.^[22], with permission from AIP Publishing.