Abstract Colorless crystals of the barium rare earth hydrogarnets Ba3[RE(OH)6]2 (RE = Sc, Y, Ho–Lu) were synthesized under hydroflux conditions with KOH at about T = 200 °C starting from the respective RE 2O3 and Ba (NO3)2. Single-crystal X-ray diffraction analysis on these distorted rhombic dodecahedra revealed the cubic space group Ia 3 ‾ $‾{3}$ d (no. 230). The crystal structures of the hydrogarnets Ba3[RE(OH)6]2 are discussed and compared with those of other hydrogarnets. The occurrence of additional reflections, which do not fulfill the reflection conditions of Ia 3 ‾ $‾{3}$ d, is analyzed and described by Renninger or λ/2 effects. A correlation is established between the space group adopted by a hydrogarnet and characteristic interatomic distances. In addition, single-crystal structure data of the strontium indium hydrogarnet Sr3[In(OH)6]2 are provided.

中文翻译：

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Hydroflux 合成和水石榴石的晶体结构 Ba3[RE(OH)6]2 (RE = Sc, Y, Ho-Lu)

摘要 钡稀土氢化石榴石 Ba3[RE(OH)6]2 (RE = Sc, Y, Ho-Lu) 的无色晶体是在 Hydroflux 条件下用 KOH 在大约 T = 200 °C 下从各自的 RE 2O3 和钡（NO3）2。对这些扭曲的菱形十二面体的单晶 X 射线衍射分析揭示了立方空间群 Ia 3 ‾ $‾{3}$ d（编号 230）。讨论了水石榴石 Ba3[RE(OH)6]2 的晶体结构，并与其他水石榴石的晶体结构进行了比较。不满足 Ia 3 ‾ $‾{3}$ d 反射条件的附加反射的发生由 Renninger 或 λ/2 效应分析和描述。水石榴石所采用的空间群与特征原子间距离之间建立了相关性。此外，