University of Marburg, Department of Chemistry and Materials Science, Max Planck Institute for Chemical Energy Conversion, Aalto-yliopisto, Aalto University
The D2h-symmetric dinuclear complex anion [U2F12]2- of pastel green Sr[U2F12] shows a hitherto unknown structural feature: The coordination polyhedra around the U atoms are edge-linked monocapped trigonal prisms, the UV atoms are therefore seven-coordinated. This leads to a U-U distance of 3.8913(6)Å. A weak UV-UV interaction is observed for the dinuclear [U2F12]2- complex and described by the antiferromagnetic exchange Jexp of circa -29.9cm-1. The crystalline compound can be easily prepared from SrF2 and β-UF5 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.
