The [U₂F₁₂]²⁻ Anion of Sr[U₂F₁₂]

The D 2 h ‐symmetric dinuclear complex anion [U 2 F 12 ] 2− of pastel green Sr[U 2 F 12 ] shows a hitherto unknown structural feature: The coordination polyhedra around the U atoms are edge‐linked monocapped trigonal prisms, the U V atoms are therefore seven‐coordinated. This leads to a U–U distance of 3.8913(6) Å. A weak U V –U V interaction is observed for the dinuclear [U 2 F 12 ] 2− complex and described by the antiferromagnetic exchange J exp of circa −29.9 cm −1 . The crystalline compound can be easily prepared from SrF 2 and β‐UF 5 in anhydrous hydrogen fluoride (aHF) at room temperature. It was studied by means of single crystal X‐ray diffraction, IR, Raman and UV/VIS spectroscopy, magnetic measurements, and by molecular as well as by solid‐state quantum chemical calculations.