title: Ultrafast X-Ray Diffraction Studies of the Phase Transitions and Equation of State of Scandium Shock Compressed to 82 GPa.
abstract: Using x-ray diffraction at the Linac Coherent Light Source x-ray free-electron laser, we have determined simultaneously and self-consistently the phase transitions and equation of state (EOS) of the lightest transition metal, scandium, under shock compression. On compression scandium undergoes a structural phase transition between 32 and 35 GPa to the same bcc structure seen at high temperatures at ambient pressures, and then a further transition at 46 GPa to the incommensurate host-guest polymorph found above 21 GPa in static compression at room temperature. Shock melting of the host-guest phase is observed between 53 and 72 GPa with the disappearance of Bragg scattering and the growth of a broad asymmetric diffraction peak from the high-density liquid.
authors.affiliation: SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom.
authors.forename: R
authors.initials: R
authors.lastname: Briggs
authors.affiliation: SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom.
authors.forename: M G
authors.initials: MG
authors.lastname: Gorman
authors.affiliation: SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom.
authors.forename: A L
authors.initials: AL
authors.lastname: Coleman
authors.affiliation: SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom.
authors.forename: R S
authors.initials: RS
authors.lastname: McWilliams
authors.affiliation: European XFEL, Albert-Einstein-Ring 19, D-22761 Hamburg, Germany.
authors.forename: E E
authors.initials: EE
authors.lastname: McBride
authors.affiliation: Department of Physics, Clarendon Laboratory, Parks Road, University of Oxford, Oxford OX1 3PU, United Kingdom.
authors.forename: D
authors.initials: D
authors.lastname: McGonegle
authors.affiliation: Department of Physics, Clarendon Laboratory, Parks Road, University of Oxford, Oxford OX1 3PU, United Kingdom.
authors.forename: J S
authors.initials: JS
authors.lastname: Wark
authors.affiliation: Atomic Weapons Establishment, Aldermaston, Reading RG7 4PR, United Kingdom.
authors.forename: L
authors.initials: L
authors.lastname: Peacock
authors.affiliation: Atomic Weapons Establishment, Aldermaston, Reading RG7 4PR, United Kingdom.
authors.forename: S
authors.initials: S
authors.lastname: Rothman
authors.affiliation: Atomic Weapons Establishment, Aldermaston, Reading, RG7 4PR, United Kingdom and Institute of Shock Physics, Imperial College London, SW7 2AZ, United Kingdom.
authors.forename: S G
authors.initials: SG
authors.lastname: Macleod
authors.affiliation: Shock and Detonation Physics, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Bolme
authors.affiliation: Shock and Detonation Physics, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545, USA.
authors.forename: A E
authors.initials: AE
authors.lastname: Gleason
authors.affiliation: Lawrence Livermore National Laboratory, 6000 East Avenue, Livermore, California 94500, USA.
authors.forename: G W
authors.initials: GW
authors.lastname: Collins
authors.affiliation: Lawrence Livermore National Laboratory, 6000 East Avenue, Livermore, California 94500, USA.
authors.forename: J H
authors.initials: JH
authors.lastname: Eggert
authors.affiliation: Lawrence Livermore National Laboratory, 6000 East Avenue, Livermore, California 94500, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Fratanduono
authors.affiliation: Lawrence Livermore National Laboratory, 6000 East Avenue, Livermore, California 94500, USA.
authors.forename: R F
authors.initials: RF
authors.lastname: Smith
authors.affiliation: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
authors.forename: E
authors.initials: E
authors.lastname: Galtier
authors.affiliation: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
authors.forename: E
authors.initials: E
authors.lastname: Granados
authors.affiliation: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
authors.forename: H J
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
authors.forename: B
authors.initials: B
authors.lastname: Nagler
authors.affiliation: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
authors.forename: I
authors.initials: I
authors.lastname: Nam
authors.affiliation: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Xing
authors.affiliation: SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Mayfield Road, Edinburgh, EH9 3JZ, United Kingdom and Research Complex at Harwell, Didcot, Oxon OX11 0FA, United Kingdom.
authors.forename: M I
authors.initials: MI
authors.lastname: McMahon