First‐Principles Calculation of Basic Properties of Rhombohedral Hafnium Oxide with Space Group R3

Structural, mechanical, and electrophysical properties of rhombohedral hafnium oxide (r‐HfO 2 ) with space group R 3, as well as properties of HfO 2 , ZrO 2 , and Hf 0.5 Zr 0.5 O 2 with space group Pca 2 1 are studied using quantum chemical calculations. The characteristic diffraction peak of 2 θ r‐HfO 2 is close to the characteristic diffraction peaks of tetragonal (t‐HfO 2 ) and orthorhombic (f‐HfO 2 ) hafnium oxide. The value of bulk modulus is 231 GPa, which is larger than one of the orthorhombic structures. The values of high intensity peaks of Raman spectrum are 670 and 540 cm −1 . The bandgap width is 5.8 eV and the average value of dielectric constant is 35.34, which is higher than one of orthorhombic hafnium oxide.