Ultra-fast x-ray diffraction studies of the phase transitions and equation of state of scandium shock-compressed to 82 GPa

Journal article

Using x-ray diffraction at the LCLS x-ray free electron laser, we have determined simultaneously and self-consistently the phase transitions and equation-of-state 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: Briggs, B; Gorman, M; Coleman, A; McWilliams, R; McBride, E

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Physical Society
• Journal: Physical Review Letters
• Volume: 118
• Issue: 2
• Article number: 025501
• Publication date: 2017-01-09
• Acceptance date: 2016-10-23
• DOI: 10.1103/PhysRevLett.118.025501
• EISSN: 1079-7114
• ISSN: 0031-9007