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

Structural, mechanical, and electrophysical properties of rhombohedral hafnium oxide (r‐HfO2) with space group <italic>R</italic>3, as well as properties of HfO2, ZrO2, and Hf0.5Zr0.5O2 with space group <italic>Pca</italic>21 are studied using quantum chemical calculations. The characteristic diffraction peak of 2<italic>θ</italic> r‐HfO2 is close to the characteristic diffraction peaks of tetragonal (t‐HfO2) and orthorhombic (f‐HfO2) 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. [ABSTRACT FROM AUTHOR]