We present an experimental and theoretical study of dysprosium metal compressed in the soft pressure transmitting medium Ne up to 182 and 300 GPa, respectively. Angle-dispersive x-ray powder diffraction data from each of the high-pressure polymorphs shows anisotropic compression behavior indicating changes to the electron density distribution throughout its polymorphic landscape. We compare the monoclinic $\left(m\mathrm{C}4\right)$ and orthorhombic $\left(o\mathrm{F}16\right)$ structures for the collapsed structure for Dy above 82 GPa and verify that the $o\mathrm{F}16$ structure offers a better fit to our data than the previously reported $m\mathrm{C}4$ structure. Further, we have found that the $o\mathrm{F}16$ structure undergoes similar anisotropic compression of its lattice parameters, with a turning point above 160 GPa; suggesting a potential phase transition at pressures much higher than achieved in this study. Density functional theory calculations show the likely candidate for this new high-pressure phase is the isosymmetric $o\mathrm{F}8$ structure, which is predicted to be lower in energy than the $o\mathrm{F}16$ structure above 275 GPa.

中文翻译：

---

在氖压力介质中压缩至 182 GPa 的镝金属的高压结构系统

我们提出了在软压力传输介质 Ne 中压缩的镝金属的实验和理论研究，分别高达 182 和 300 GPa。来自每个高压多晶型物的角色散 X 射线粉末衍射数据显示各向异性压缩行为，表明整个多晶型物的电子密度分布发生了变化。我们比较单斜$\left(米\mathrm{C}4\right)$和正交的$\left(○\mathrm{F}16\right)$Dy 高于 82 GPa 的折叠结构的结构，并验证$○\mathrm{F}16$结构比之前报道的更适合我们的数据$米\mathrm{C}4$结构体。此外，我们发现，$○\mathrm{F}16$结构的晶格参数经历了类似的各向异性压缩，转折点在 160 GPa 以上；表明潜在的相变压力远高于本研究中的压力。密度泛函理论计算表明，这种新高压相的可能候选者是等对称$○\mathrm{F}8$结构，预计其能量低于$○\mathrm{F}16$结构高于 275 GPa。