The Fermi model in describing phase transitions initiated by pressure variation

• Published in: Bulletin of the Russian Academy of Sciences. Physics Vol. 77; no. 7; pp. 908 - 912
• Main Authors: Naskalova, O. V., Smolin, A. Yu, Klimova, E. N., Kuznetsova, E. M.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.07.2013; Springer Nature B.V
• Subjects: Atomic Power Engineering and Nuclear Technologies” (The 62nd International Conference on Nuclear Spectroscopy and the Structure of Atomic Nuclei); Ground state; Hadrons; Hafnium oxide; Heavy Ions; Mathematical models; Nuclear Physics; Phase transitions; Physics; Physics and Astronomy; Pressure dependence; Proceedings of the International Conference “Nucleus-2012”. “Fundamental Problems of Nuclear Physics; Quantum chemistry; Stiffness; Mott Model; Baddeleyite; Quantum Chemistry Model; Metal Insulator; Fermi Model
• ISSN: 1062-8738; 1934-9432
• DOI: 10.3103/S1062873813070162

Having analyzed the pressure dependence of volume V (σ), we demonstrate that the mechanism of the phase transition in HfO 2 corresponds to the Fermi model. This indicates that at σ = 10 GPa, the ground state of Hf ions changes. Within the Fermi model, the stiffness moduli in the phases stable at σ < 10 GPa and σ > 10 GPa are calculated. It is shown that the results obtained are in better agreement with the well-known experiment than the results obtained in the framework of the quantum chemistry model (ab initio calculations) and the Birch-Murnaghan equation of state.