Chemey Alexander T, Celis-Barros Cristian, Huang Kevin, Sperling Joseph M, Windorff Cory J, Baumbach Ryan E, Graf David E, Páez-Hernández Dayán, Ruf Michael, Hobart David E, Albrecht-Schmitt Thomas E
Department of Chemistry and Biochemistry , Florida State University , Tallahassee , Florida 32306 , United States.
National High Magnetic Field Laboratory , Florida State University , Tallahassee , Florida 32306 , United States.
Inorg Chem. 2019 Jan 7;58(1):637-647. doi: 10.1021/acs.inorgchem.8b02800. Epub 2018 Dec 20.
The simple system of tetraammonium octafluorouranate is employed to derive a fundamental understanding of the uranium-fluorine interaction. The structure is composed of isolated molecules, enabling a detailed examination of the U ( f) ion. Characterization of single-crystals by X-ray diffraction, absorption spectroscopy, and magnetic analysis up to 45 T is combined with extensive theoretical treatment by CASSCF. The influence of different active spaces and representations of the structure is examined in the context of the experimental evidence. The Interacting Quantum Atoms method (IQA) is used to examine the nature of the U-F bond, concluding that there is a non-negligible degree of covalent character (9% of the total bond energy) in [UF]. For the structural and theoretical reasons discussed herein, it is proposed that the structure of (NH)UF may be appropriately employed as a benchmark compound for future theoretical characterization of U(IV).
采用八氟铀酸四铵的简单体系来深入理解铀 - 氟相互作用。该结构由孤立分子组成，便于对U(IV)离子进行详细研究。通过X射线衍射、吸收光谱以及高达45 T的磁性分析对单晶进行表征，并结合CASSCF进行广泛的理论处理。在实验证据的背景下，研究了不同活性空间和结构表示的影响。使用相互作用量子原子方法（IQA）来研究U - F键的性质，得出[UF₈]²⁻中存在不可忽略程度的共价特性（占总键能的9%）。基于本文讨论的结构和理论原因，建议将(NH₄)₂UF₈的结构适当地用作未来U(IV)理论表征的基准化合物。
