Identification of Phase Transitions and Metastability in Dynamically Compressed Antimony Using Ultrafast X-Ray Diffraction
Identification of Phase Transitions and Metastability in Dynamically Compressed Antimony Using Ultrafast X-Ray Diffraction
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DOI：
10.1103/physrevlett.122.255704
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发表时间：
2019-06-28
影响因子：
8.6
通讯作者：
McMahon, M. I.
中科院分区：
文献类型：
--
作者：
Coleman, A. L.;Gorman, M. G.;McMahon, M. I.
在LCLS X射线自由电子激光器的超快X射线衍射已被用来解决冲击压缩到59 GPa下的锑的结构行为。锑被认为是转化为无公度，主客体相Sb-II在类似于11 GPa，它的形式与有序的客人原子链的纳秒时间尺度。高压bcc相Sb-III在上面观察到类似于15 GPa，比静态压缩研究低约8 GPa，并且在38和59 GPa之间获得混合Sb-III/液体衍射。在8 ~ 12 GPa之间，在Sb-Ⅰ的正常稳定场之外，还观察到一个在静态压缩下不存在的附加相Sb-Ⅰ ′，它类似于Sb-Ⅰ，但有一个分辨的Peierls畸变。无公度的Sb-II高压相可以在释放到环境压力时亚稳定地恢复，其中它稳定超过10 ns。
Ultrafast x-ray diffraction at the LCLS x-ray free electron laser has been used to resolve the structural behavior of antimony under shock compression to 59 GPa. Antimony is seen to transform to the incommensurate, host-guest phase Sb-II at similar to 11 GPa, which forms on nanosecond timescales with ordered guest-atom chains. The high-pressure bcc phase Sb-III is observed above similar to 15 GPa, some 8 GPa lower than in static compression studies, and mixed Sb-III/liquid diffraction are obtained between 38 and 59 GPa. An additional phase which does not exist under static compression, Sb-I', is also observed between 8 and 12 GPa, beyond the normal stability field of Sb-I, and resembles Sb-I with a resolved Peierls distortion. The incommensurate Sb-II high-pressure phase can be recovered metastably on release to ambient pressure, where it is stable for more than 10 ns.