1. Ultra-fast yttrium hydride chemistry at high pressures via non-equilibrium states induced by x-ray free electron laser
- Author
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Siska, Emily, Smith, G. Alexander, Villa-Cortes, Sergio, Conway, Lewis J., Husband, Rachel J., Van Cleave, Joshua, Petitgirard, Sylvain, Cerantola, Valerio, Appel, Karen, Baehtz, Carsten, Bouffetier, Victorien, Dwiwedi, Anand, Göde, Sebastian, Gorkhover, Taisia, Konopkova, Zuzana, Hosseini, Mohammad, Kuschel, Stephan, Laurus, Torsten, Nakatsutsumi, Motoaki, Strohm, Cornelius, Sztuk-Dambietz, Jolanta, Zastrau, Ulf, Smith, Dean, Lawler, Keith V., Pickard, Chris J., Schwartz, Craig P., and Salamat, Ashkan
- Subjects
Condensed Matter - Materials Science - Abstract
Controlling the formation and stoichiometric content of desired phases of materials has become a central interest for the study of a variety of fields, notably high temperature superconductivity under extreme pressures. The further possibility of accessing metastable states by initiating reactions by x-ray triggered mechanisms over ultra-short timescales is enabled with the development of x-ray free electron lasers (XFEL). Utilizing the exceptionally high brilliance x-ray pulses from the EuXFEL, we report the synthesis of a previously unobserved yttrium hydride under high pressure, along with non-stoichiometric changes in hydrogen content as probed at a repetition rate of 4.5\,MHz using time-resolved x-ray diffraction. Exploiting non-equilibrium pathways we synthesize and characterize a hydride with yttrium cations in an \textit{A}15 structure type at 125\,GPa, predicted using crystal structure searches, with a hydrogen content between 4.0--5.75 hydrogens per cation, that is enthalpically metastable on the convex hull. We demonstrate a tailored approach to changing hydrogen content using changes in x-ray fluence that is not accessible using conventional synthesis methods, and reveals a new paradigm in metastable chemical physics.
- Published
- 2023