Pressure-induced structural phase transitions of zirconium: an ab initio study based on statistical ensemble theory

Bo-Yuan Ning

doi:10.1088/1361-648X/ac9bbf

Pressure-induced structural phase transitions of zirconium: an ab initio study based on statistical ensemble theory

J Phys Condens Matter. 2022 Oct 28;34(50). doi: 10.1088/1361-648X/ac9bbf.

Author

Bo-Yuan Ning^{1

2

3}

Affiliations

¹ Institute of Modern Physics, Fudan University, Shanghai 200433, People's Republic of China.
² Applied Ion Beam Physics Laboratory, Fudan University, Shanghai 200433, People's Republic of China.
³ Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, People's Republic of China.

PMID: 36261047
DOI: 10.1088/1361-648X/ac9bbf

Abstract

Recently, we put forward a direct integral approach to solve the partition function with ultrahigh efficiency and precision, which enables the rigorous ensemble theory to investigate phase behaviors of realistic condensed matters and has been successfully applied to the phase transition of vanadium metal (Ninget al2022J. Phys.: Condens. Matter34425404). In this work, the approach is applied to the structural phase transitions of zirconium metal under compressions up to 160 GPa and ultrahigh calculation precision is achieved. For the obtained equation of state with pressure over 40 GPa, the deviations from latest experiments are within0.7%and the computed transition pressure ofα→ωis 6.93 GPa, which is about five times larger than previous theoretical predictions and in excellent agreement with the measured range of 5-15 GPa. Our results support the argument that there is no existence of the isostructural phase transition of Zr metal that was asserted by recent experimental observations.

Keywords: extreme-condition physics; free energy calculation; structural phase transition.