Probing liquid-liquid phase transitions under dynamic compression: an X-ray diffraction and <i>ab initio</i> MD study of selenium

 · Invited

Abstract

One of the most interesting phenomena of non-crystalline materials is polyamorphism, or the ability of an amorphous material, with medium range order, to exist in several distinct modifications. In liquids, the transition between these states has been termed the liquid-liquid phase transition (LLPT) and has been observed experimentally under static compression experiments in several materials. In selenium, ab initio calculations have shown significant changes in the liquid structure with increasing pressure, yet experimental data at high-pressure is limited. Even less is known regarding the evolution of the liquid structure under rapid shock compression and whether a LLPT between complex liquid structures can occur on nanosecond timescales.
Here we report on femtosecond X-ray diffraction measurements of the LLPT in selenium following shock compression and release and find that the liquid structure transformations are dramatic and we show that they can occur on nanosecond timescales. The results are supported by molecular dynamic simulations of the liquid state at a range of pressure, temperature, density states covering the LLPT. Experiments were performed at the Matter at Extreme Conditions end-station of the Linac Coherent Light Source (LCLS). This work was performed under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344.

*This work was performed under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344. Use of the Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515.

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Presenters

  • Richard Briggs

    • Lawrence Livermore Natl Lab

Authors

  • Richard Briggs

    • Lawrence Livermore Natl Lab

  • Amy L Coleman

    • Lawrence Livermore Natl Lab

  • Shuai Zhang

    • Laboratory for Laser Energetics, University of Rochester
    • University of Rochester
    • Lawrence Livermore Natl Lab

  • David R McGonegle

    • University of Oxford
    • Oxford University

  • Federica Coppari

    • Lawrence Livermore Natl Lab

  • Amalia fernandez

    • Lawrence Livermore Natl Lab

  • Martin G Gorman

    • Lawrence Livermore Natl Lab

  • Michelle C Marshall

    • Lawrence Livermore Natl Lab

  • Raymond Smith

    • Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab
    • Lawrence Livemore

  • Orianna Ball

    • University of Edinburgh

  • Ryan S McWilliams

    • University of Edinburgh

  • Vitali Prakapenka

    • Center for Advanced Radiation Sources, University of Chicago
    • GSECARS, University of Chicago
    • Center for Advanced Radiation Sources
    • Center for Advanced Radiation Source, University of Chicago

  • Conor Krill

    • John Hopkins University

  • Vinay Rastogi

    • John Hopkins University

  • June Wicks

    • Johns Hopkins University
    • John Hopkins University

  • Cynthia Bolme

    • Los Alamos National Laboratory

  • Philip Heimann

    • Los Alamos National Laboratory
    • SLAC
    • SLAC national accelerator laboratory

  • Eric Cunningham

    • SLAC national accelerator laboratory

  • Haeja Lee

    • Los Alamos National Laboratory
    • SLAC National Accelerator Laboratory
    • SLAC national accelerator laboratory

  • Malcolm I McMahon

    • University of Edinburgh

  • Jon Henry Eggert

    • Lawrence Livermore Natl Lab
    • Lawrence Livermore National Laboratory

  • Dayne Fratanduono

    • Lawrence Livermore Natl Lab