Abstract Two new structural types of BaREGeO4(OH) and BaRE10(GeO4)4O8 (RE = Ho3+,Er3+) single crystals were synthesized via high-temperature and high-pressure hydrothermal synthesis. The BaREGeO4(OH) compounds were found to crystallize in the orthorhombic space group Pbca. BaHoGeO4(OH) is used as a representative of the family with cell parameters of a = 5.7175(2) A, b = 10.1556(5) A, c = 10.6189(9) A and V = 964.97(8) A3. The BaREGeO4(OH) structure contains a one-dimensional chain of rare-earth polyhedra linked through edge sharing of oxygen atoms. High density BaRE10(GeO4)4O8 crystals crystallize in the monoclinic space group C2/m and feature a sheet like arrangement of rare-earth oxide polyhedra with Keggin-like features. BaHo10(GeO4)4O8 is used as a representative of this structure type with cell parameters of a = 12.4533(8) A, b = 7.2008(5) A, c = 12.0034(8) A, β = 100.183(2)⁰ and V = 1059.43(12) A3. Barium polyhedra and isolated GeO4 units aid in connecting the rare earth oxide framework to extend it in three-dimensional (3-D) space. Characterization by single crystal X-ray diffraction and Raman and photoluminescence spectroscopies is reported.

中文翻译：

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2-D 和 3-D 钡稀土锗酸盐的水热晶体生长：BaREGeO4(OH) 和 BaRE10(GeO4)4O8 (RE = Ho, Er)

摘要 采用高温高压水热合成法合成了两种新型结构类型的BaREGeO4(OH)和BaRE10(GeO4)4O8(RE=Ho3+,Er3+)单晶。发现 BaREGeO4(OH) 化合物在正交空间群 Pbca 中结晶。BaHoGeO4(OH) 用作电池参数为 a = 5.7175(2) A、b = 10.1556(5) A、c = 10.6189(9) A 和 V = 964.97(8) A3 的系列的代表。BaREGeO4(OH) 结构包含一维稀土多面体链，通过氧原子的边缘共享连接。高密度 BaRE10(GeO4)4O8 晶体在单斜空间群 C2/m 中结晶，并具有片状排列的稀土氧化物多面体，具有类似 Keggin 的特征。BaHo10(GeO4)4O8 被用作这种结构类型的代表，其电池参数为 a = 12.4533(8) A, b = 7.2008(5) A，c = 12.0034(8) A, β = 100.183(2)⁰ 和 V = 1059.43(12) A3。钡多面体和孤立的 GeO4 单元有助于连接稀土氧化物框架，以将其扩展到三维 (3-D) 空间。报告了单晶 X 射线衍射和拉曼光谱和光致发光光谱的表征。