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, Dwivedi Anand, Göde Sebastian, Gorkhover Tais, Konopkova Zuzana, Hosseini-Saber S M A, Kuschel Stephan, Laurus Torsten, Nakatsutsumi Motoaki, Strohm Cornelius, Sztuk-Dambietz Jolanta, Zastrau Ulf, Smith Dean, Lawler Keith V, Pickard Chris J, Schwartz Craig P, Salamat Ashkan
Nevada Extreme Conditions Laboratory, University of Nevada Las Vegas, Las Vegas, Nevada 89154, United States.
Department of Chemistry & Biochemistry, University of Nevada Las Vegas, Las Vegas, Nevada 89154, United States.
J Phys Chem Lett. 2024 Oct 3;15(39):9912-9919. doi: 10.1021/acs.jpclett.4c02134. Epub 2024 Sep 20.
Controlling the formation and stoichiometric content of the desired phases of materials has become of central interest for a variety of fields. The possibility of accessing metastable states by initiating reactions by X-ray-triggered mechanisms over ultrashort time scales has been enabled by the development of X-ray free electron lasers (XFELs). 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 nonstoichiometric 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 in a Weaire-Phelan structure type at pressures as low as 125 GPa, predicted using a crystal structure search, with a hydrogen content of 4.0-5.75 hydrogens per cation, that is enthalpically metastable on the convex hull.
控制材料所需相的形成和化学计量含量已成为多个领域的核心关注点。X射线自由电子激光（XFEL）的发展使得通过在超短时间尺度上由X射线触发机制引发反应来进入亚稳态成为可能。利用欧洲XFEL产生的极高亮度的X射线脉冲，我们报告了在高压下合成了一种以前未观察到的氢化钇，并通过时间分辨X射线衍射以4.5 MHz的重复率探测了氢含量的非化学计量变化。通过利用非平衡途径，我们在低至125 GPa的压力下合成并表征了一种具有韦亚尔-费兰结构类型的氢化物，该结构通过晶体结构搜索预测，每个阳离子的氢含量为4.0 - 5.75个氢，在凸包上是焓亚稳态的。
