An ab initio study of structural phase transitions of crystalline aluminium under ultrahigh pressures based on ensemble theory

Ning, Bo-Yuan1,2,3; Zhang, Li-Yuan1,4

2023-02-05

10.1016/j.commatsci.2022.111960

COMPUTATIONAL MATERIALS SCIENCE   Impact Factor & Quartile

0927-0256

1879-0801

We recently put forward a direct integral approach to solve the partition function with ultrahigh efficiency and precision so that the rigorous ensemble theory can be applied to study the phase behaviors of realistic condensed-matter materials. In this work, the approach is used to investigate the structural phase transitions of crystalline aluminium up to 600 GPa at room temperature and the obtained equation of state is in an excellent agreement with recent experiments within 4% deviations. For the disputed transition pressures of the FCC -> HCP -> BCC, our calculated results are 194 and 361 GPa, which solely coincide with those measured by one of the experiments (Dewaele et al., 2018) within 2% and 0.3% differences respectively but deviate 13% and 5% from the others. In addition, our computations show that the axial ratio of the stable HCP structure is 1.62 and there exists discontinuities in the equation of state at the phase boundaries accompanied with subtle volume changes of -0.67% and -0.90%, all of which exactly support the observations from the experiment by Dewaele et al.

Structural phase transitions Extreme-condition physics Free-energy computation

SCI

English

Corresponding

Materials Science

Materials Science, Multidisciplinary

WOS:000904983300001

ELSEVIER

MATERIALS SCIENCE

Web of Science

1.Fudan Univ, Inst Modern Phys, Shanghai 200433, Peoples R China
2.Fudan Univ, Appl Ion Beam Phys Lab, Shanghai 200433, Peoples R China
3.Southern Univ Sci & Technol, Dept Mat Sci & Engn, Shenzhen 518055, Peoples R China
4.East China Univ Sci & Technol, Sch Phys, Shanghai 200237, Peoples R China

Ning, Bo-Yuan,Zhang, Li-Yuan. An ab initio study of structural phase transitions of crystalline aluminium under ultrahigh pressures based on ensemble theory[J]. COMPUTATIONAL MATERIALS SCIENCE,2023,218.

Ning, Bo-Yuan,&Zhang, Li-Yuan.(2023).An ab initio study of structural phase transitions of crystalline aluminium under ultrahigh pressures based on ensemble theory.COMPUTATIONAL MATERIALS SCIENCE,218.

Ning, Bo-Yuan,et al."An ab initio study of structural phase transitions of crystalline aluminium under ultrahigh pressures based on ensemble theory".COMPUTATIONAL MATERIALS SCIENCE 218(2023).