Raw data for Barium Polyhydride

Dataset relating to "Synthesis of Weaire-Phelan Barium Polyhydride". By combining pressures up to 50 GPa and temperatures of 1200 K, we synthesize the novel barium hydride, Ba8H46, stable down to 27 GPa. We use Raman spectroscopy, X-ray diffraction, and first-principles calculations to determine that this compound adopts a highly symmetric 𝑃𝑚3¯𝑛 structure with an unusual 534:1 hydrogen-to-barium ratio. This singular stoichiometry corresponds to the well-defined type-I clathrate geometry. This clathrate consists of a Weaire–Phelan hydrogen structure with the barium atoms forming a topologically close-packed phase. In particular, the structure is formed by H20 and H24 clathrate cages showing substantially weakened H–H interactions. Density functional theory (DFT) demonstrates that cubic 𝑃𝑚3¯𝑛 Ba8H46 requires dynamical effects to stabilize the H20 and H24 clathrate cages.

本数据集关联《Weaire-Phelan型多氢化钡的合成》研究。通过结合最高50 GPa（吉帕斯卡）的压力与1200 K（开尔文）的温度条件，我们成功合成了新型氢化钡Ba8H46，该化合物在低至27 GPa的压力下仍保持稳定。我们借助拉曼光谱（Raman spectroscopy）、X射线衍射（X-ray diffraction）以及第一性原理计算，确定该化合物具有高度对称的𝑃𝑚3¯𝑛结构，氢与钡的比例达到了罕见的534:1。这种特殊的化学计量比对应于结构明确的I型笼形（type-I clathrate）结构。该笼形结构以Weaire–Phelan型氢骨架为主体，钡原子则构成拓扑密堆相。具体而言，该结构由H₂₀与H₂₄笼形笼腔构成，其中氢-氢相互作用被显著削弱。密度泛函理论（Density functional theory, DFT）表明，立方相𝑃𝑚3¯𝑛结构的Ba8H46需要动力学效应来稳定H₂₀与H₂₄笼形笼腔。