Fig.5 Equation of state for different crystalline phases of HfO2 (V is the volume of the cell. Solid lines and crosses mark the results of DFT calculations and DP model predictions, respectively)[103] (a), phonon spectra of HfO2P21/c, Pbca, and Pca21phases[103] (b), energy barrier calculations between multiple crystalline phases of HfO2 (Solid lines are DFT calculations, and hollow circles are DP predictions)[103] (c), probability distributions of the local displacement of oxygen atoms along the [010] direction (d[010]) at different temperatures for a pressure of 0 GPa (Inset shows the distribution of the displacements of oxygen atoms along the [100], [010], and [001] directions at 400 K) (d), and temperature increase-driven changes in the lattice constant and in the average value of d[010], indicating the occurrence of a phase transition (e)
|