Phase transitions and new states under extreme conditions from first-principles*

High pressure is an important method to modify the free energy surface of materials and overcome the barriers for synthesizing new functional materials. On the other hand, crystal structure search based on ab initio calculations has been successfully used to prediction new materials. In this talk, I will introduce some of our recent work on theoretical prediction on high pressure phase transitions, functional materials with interesting properties, and new states of matter under extreme conditions, such as superionic states.

REFERENCE
1. C. Liu, et al., "Multiple superionic states in helium-water compounds", Nature Physics 15, 1065 (2019).
2. Q.Y. Gu, et al., "Superconducting single-layer T-graphene and novel synthesis routes", Chin. Phys. Lett. 36, 097401 (2019) (Express letter)
3. H. Gao, et al., "Improve the performance of machine-learning potentials by optimizing descriptors", J. Chem. Phys. 150, 244110 (2019).
4. J.F. Wu, et al., "Ground states of Au2Pb and pressure-enhanced superconductivity", Phys. Rev. B 100, 060103 (R) (2019).
5. P.C. Lu, et al., "Robust double Weyl semimetal phase in a nonmagnetic hexagonal lattice system", Phys. Rev. B 99, 165119 (2019).
6. H. Gao, et al., "Prediction of pressure-induced stabilization of noble-gas-atom compounds with alkali oxides and alkali sulfides", Phys. Rev. Mater. 3, 015002 (2019).