TY  - JOUR
AU  - Husband, Rachel
AU  - Liermann, Hanns-Peter
AU  - McHardy, James
AU  - Mcwilliams, Ryan Stewart
AU  - Goncharov, Alexander
AU  - Prakapenka, Vitali
AU  - Edmund, Eric
AU  - Chariton, Stella
AU  - Konopkova, Zuzana
AU  - Strohm, Cornelius
AU  - Sanchez-Valle, Carmen
AU  - Frost, Mungo
AU  - Andriambariarijaona, Leon
AU  - Appel, Karen
AU  - Baehtz, Carsten
AU  - Ball, Orianna
AU  - Briggs, Richard
AU  - Buchen, Johannes
AU  - Cerantola, Valerio
AU  - Choi, Jinhyuk
AU  - Coleman, Amy
AU  - CYNN, HYUNCHAE
AU  - Dwivedi, Anand
AU  - Graafsma, Heinz
AU  - Hwang, Huijeong
AU  - Koemets, Egor
AU  - Laurus, Torsten
AU  - Lee, Yongjae
AU  - Li, Xinyang
AU  - Marquardt, Hauke
AU  - Mondal, Anshuman
AU  - Nakatsutsumi, Motoaki
AU  - NINET, Sandra
AU  - Pace, Edward
AU  - Pépin, Charles
AU  - Prescher, Clemens
AU  - Stern, Stephan
AU  - Sztuk-Dambietz, Jolanta
AU  - Zastrau, Ulf
AU  - McMahon, Malcolm
TI  - Phase transition kinetics of superionic H<sub>2</sub>O ice phases revealed by MHz XFEL heating experiments
JO  - Nature Communications
VL  - 15
IS  - 1
SN  - 2041-1723
CY  - [London]
PB  - Nature Publishing Group UK
M1  - PUBDB-2024-05368
SP  - 8256
PY  - 2024
N1  - We acknowledge support from the Deutsche For-schungsgemeinschaft (DFG) Research Unit FOR 2440 grants SA2585/5-1 (R.J.H, A.M., C.S.V., and H.P.L) and AP262/2-2 (K.A.).
AB  - H2O transforms to two forms of superionic (SI) ice at high pressures and temperatures, which contain highly mobile protons within a solid oxygen sublattice. Yet the stability field of both phases remains debated. Here, we present the results of an ultrafast X-ray heating study utilizing MHz pulse trains produced by the European X-ray Free Electron Laser to create high temperature states of H2O, which were probed using X-ray diffraction during dynamic cooling. We confirm an isostructural transition during heating in the 26-69 GPa range, consistent with the formation of SI-bcc. In contrast to prior work, SI-fcc was observed exclusively above  50 GPa, despite evidence of melting at lower pressures. The absence of SI-fcc in these runs is attributed to short heating timescales and the pressure-temperature path induced by the pump-probe heating scheme in which H2O was heated above its melting temperature before the observation of quenched crystalline states, based on the earlier theoretical prediction that SI-bcc nucleates more readily from the fluid than SI-fcc. Our results may have implications for the stability of SI phases in ice-rich planets, for example during dynamic freezing, where the preferential crystallization of SI-bcc may result in distinct physical properties across mantle ice layers.
LB  - PUB:(DE-HGF)16
C6  - pmid:39313509
UR  - <Go to ISI:>//WOS:001320768800004
DO  - DOI:10.1038/s41467-024-52505-0
UR  - https://bib-pubdb1.desy.de/record/612515
ER  -