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Figure 10
Envelope diagrams [(c) and (d)] of the negative Laplacian distribution (charge concentration) around the U atom in the UF6− anion plotted at the −280 e Å−5­ level. The corresponding (3, +3) critical points (maxima of charge concentration) of the Laplacian distribution [(a) and (b)] are depicted as red spheres. The directions of the fluorine ligands are indicated by labels, except for the axial F2 atoms in (b) and (d), where the axial ligands are above and below the plane of the image. When depicted, thermal ellipsoids are drawn at the 99% probability level. Although these distributions were obtained from model 1c, nearly identical distributions are obtained from model 1b. U–cp distances are in the range 0.37–0.38 Å for the 14 nearest cps and 1.075 Å for the distant cp. The F2–cp distance is 1.001 Å.

IUCrJ
Volume 6| Part 5| September 2019| Pages 895-908
ISSN: 2052-2525
https://doi.org/10.1107/S2052252519010248