The 4th International Conference on Matter and Radiation at Extremes (ICMRE 2019)

328 / 2019-02-26 11:19:05

Crystal structure prediction method and its applications at high pressure

Crystal structure prediction; High pressure

Plenary track > High Pressure Physics and Materials Science

Crystal structure prediction method and its applications at high pressure

Yanchao Wang

State Key Lab of Superhard Materials& Innovation Center for Computational Physics Methods and Software, College of Physics, Jilin University, Changchun 130012, China
*Email: wyc@calypso.cn
Atomistic structures of materials occupy a central and often critical role, when establishing a correspondence between materials performance and their basic compositions. Theoretical prediction of atomistic structures of materials with the only given information of chemical compositions becomes crucially important, but it is extremely difficult as it basically involves in classifying a huge number of energy minima on the lattice energy surface. To tackle the problems, we have developed an efficient CALYPSO (Crystal structural AnLYsis by Particle Swarm Optimization) approach [1-2] for structure prediction from “scratch” based on particle swarm optimization algorithm by taking the advantage of swarm intelligence and the spirit of structures smart learning. The method has been coded into CALYPSO software (http://www.calypso.cn).CALYPSO is free for academic use and has generated over 750 high-profile publications. Currently, CALYPSO users are over 2300 and distributed world-widely over 60 countries.
Currently, CALYPSO method is able to predict structures of three-dimensional crystals, isolated clusters or molecules [3], surface reconstructions [4], and two-dimensional layers [5]. The applications of CALYPSO into purposed materials design of layered materials [6], high-pressure superconductors [7], and superhard materials [8] were successfully made. In this work, we applied CALYPSO method to explore the stabilities of Ca-O and H-O compounds at high pressures. We find some thermodynamically stable structures under pressure. These stable structures are found at pressures that are now becoming accessible to high-pressure technique. The present results define new players to buffer oxygen fugacity and might provide important insights for understanding of the Earth’s or other exoplanetary interiors.

Keywords: Crystal structure prediction; High pressure

References:
[1] Y. Wang, J. Lv, L.Zhu, and Y. Ma, Phys. Rev. B, 2010, 82, 094116.
[2] Y. Wang, J. Lv, L.Zhu, and Y. Ma, Comput. Phys. Commun. 183, 2063 (2012).
[3] J. Lv, Y. Wang, L.Zhu, and Y. Ma, J. Chem. Phys. 137, 084104 (2012).
[4] S. Lu, Y. Wang, H. Liu, M. Miao, and Y. Ma, Nature Commun. (in review).
[5] Y. Wang, et al., J. Chem. Phys. 137, 224108 (2012).
[6]X. Luo, et al., J. Am. Chem. Soc. 133, 16285 (2011).
[7] H. Wang, J. S. Tse, K. Tanaka, T. Iitaka, and Y. Ma, Proc. Natl. Acad. Sci. USA, 2012, 109, 6463-6466.
[8]X. Zhang, et al., J. Chem. Phys. 138, 114101 (2013).