Wassermann Tobias B, Sachs Malte, Etter Martin, Kraus Florian
Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany.
Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, 22607 Hamburg, Germany.
Inorg Chem. 2025 Apr 14;64(14):7088-7095. doi: 10.1021/acs.inorgchem.5c00450. Epub 2025 Apr 1.
Single crystals of uranium trifluoride, UF, were obtained for the first time via gas-phase crystallization, enabling the resolution of its crystal structure using single-crystal X-ray diffraction (SCXRD). The study reveals that UF crystallizes isotypic to the tysonite structure type in the trigonal space group 3̅1 (No. 165, 24, ) with lattice parameters = 7.1510(2), = 7.3230(4) Å, and = 324.30() Å, = 6, at = 100 K, resolving long-standing structure model ambiguities from prior studies based on powder diffraction. Merohedral twinning complicates the diffraction data by simulating the wrong Laue class 6/. Complementary quantum chemical calculations support the findings from this experiment, confirming its local energetic minimum. The inversion center in the crystal structure of UF precludes the previously predicted ferroelectricity.
首次通过气相结晶法获得了三氟化铀（UF₃）的单晶，从而能够利用单晶X射线衍射（SCXRD）解析其晶体结构。研究表明，UF₃在100 K下结晶为三方空间群R3̅m（编号165，hR，）中的钛钇矿结构类型的同型体，晶格参数a = 7.1510(2)，c = 7.3230(4) Å，V = 324.30( ) ų，Z = 6，解决了先前基于粉末衍射研究中存在的长期结构模型模糊性问题。merohedral孪晶通过模拟错误的劳厄类6/m使衍射数据复杂化。补充性量子化学计算支持了该实验的结果，证实了其局部能量最小值。UF₃晶体结构中的对称中心排除了先前预测的铁电性。
