Abstract The new samarium germanide SmGe3 is obtained by high-pressure high-temperature synthesis of pre-reacted mixtures of samarium and germanium at a pressure of 9.5 GPa and temperatures between 1073 and 1273 K. SmGe3 decomposes at 470(5) K into SmGe2, α-Sm3Ge5 and a hitherto unknown phase. SmGe3 exhibits a superstructure of the cubic Cu3Au-type. Transmission electron microscopy measurements of crystalline particles and prepared lamellae indicate a high density of defects on the nanoscale. Selected area electron diffraction and elaborate X-ray powder diffraction measurements consistently indicate a 2a 0 × 2a 0 × 2a 0 superstructure adopting space group F m 3 ¯ m $Fm\overline{3}m$ with a = 8.6719(2) Å.

中文翻译：

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SmGe3 的高压合成

摘要 钐锗的预反应混合物在 9.5 GPa 的压力和 1073 至 1273 K 的温度下，通过高压高温合成得到新的锗化钐 SmGe3。SmGe3 在 470(5) K 分解为 SmGe2， α-Sm3Ge5 和迄今为止未知的相。SmGe3 表现出立方 Cu3Au 型的超结构。晶体颗粒和制备的薄片的透射电子显微镜测量表明纳米级缺陷的高密度。选区电子衍射和精细的 X 射线粉末衍射测量一致表明 2a 0 × 2a 0 × 2a 0 超结构采用空间群 F m 3 ¯ m $Fm\overline{3}m$，a = 8.6719(2) Å。