Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada.
Geophysical Laboratory, Carnegie Institution of Washington, NW, Washington, DC 20015, USA.
J Chem Phys. 2017 Jun 21;146(23):234506. doi: 10.1063/1.4986245.
A combined theoretical and experimental study of lithium palladium deuteride (LiPdD) subjected to pressures up to 50 GPa reveals one structural phase transition near 10 GPa, detected by synchrotron powder x-ray diffraction, and metadynamics simulations. The ambient-pressure tetragonal phase of LiPdD transforms into a monoclinic C2/m phase that is distinct from all known structures of alkali metal-transition metal hydrides/deuterides. The structure of the high-pressure phase was characterized using ab initio computational techniques and from refinement of the powder x-ray diffraction data. In the high-pressure phase, the PdD complexes lose molecular integrity and are fused to extended [PdD] chains. The discovered phase transition and new structure are relevant to the possible hydrogen storage application of LiPdD and alkali metal-transition metal hydrides in general.
对锂钯氘化物（LiPdD）在高达 50 GPa 压力下的理论和实验综合研究表明，在 10 GPa 附近存在一个结构相变，通过同步辐射粉末 X 射线衍射和元动力学模拟检测到了该相变。LiPdD 的环境压力四方相转变为不同于所有已知的碱金属-过渡金属氢化物/氘化物结构的单斜 C2/m 相。利用从头算计算技术和粉末 X 射线衍射数据的精修，对高压相的结构进行了表征。在高压相中，PdD 配合物失去分子完整性，并融合成扩展的[PdD]链。所发现的相变和新结构与 LiPdD 以及一般碱金属-过渡金属氢化物的可能储氢应用有关。
