Identification of Phase Transitions and Metastability in Dynamically Compressed Antimony Using Ultrafast X-Ray Diffraction.

摘要: Ultrafast x-ray diffraction at the LCLS free electron laser has been used to resolve structural behavior of antimony under shock compression 59 GPa. Antimony is seen transform incommensurate, host-guest phase Sb-II ∼11  GPa, which forms on nanosecond timescales with ordered guest-atom chains. The high-pressure bcc Sb-III observed above ∼15  GPa, some 8 GPa lower than in static studies, and mixed Sb-III/liquid are obtained between 38 An additional does not exist compression, Sb-I^{'}, also 8 12 GPa, beyond normal stability field Sb-I, resembles Sb-I a resolved Peierls distortion. incommensurate can be recovered metastably release ambient pressure, where it stable for more 10 ns.