Consecutive Peierls distortions and high-pressure phase transitions in YH3

Article

关键词: YTTRIUM TRIHYDRIDE;    PSEUDOPOTENTIALS;    FILMS;    YD3;   

DOI  :  10.1103/PhysRevB.81.140104

来源: SCIE

【 摘 要 】

High-pressure phase transformations in YH3 were investigated using the evolutionary algorithm for structural searches. A series of phase transformations are predicted with three lowest enthalpy phases identified. Two consecutive Peierls distortions within the hcp and fcc cells result into two low-pressure structures, the previously identified P (3) over bar c1 structure and a predicted C2/m structure. The P (3) over bar c1 structure transforms to a C2/m structure at 12 GPa and stabilizes to a fcc structure at 38 GPa. The predicted properties of the C2/m structure agree well with experimental observation. At 200 GPa, the fcc structure transforms to a hcp structure. At 214 GPa, a transformation analogous to a Burgers deformation becomes more favored in the hcp form and this results in a stable Cmcm structure.

【 授权许可】

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