Another notable feature of the lone-pair-fluoride-ion spatial distribution function is that the intense feature corresponding to fluoride ions occupying tetrahedral sites is angularly diffuse. While some of this effect can be attributed to movement of these fluoride ions within their tetrahedral sites, it would be surprising for such movement to preserve the Sn-F separation. An alternative process that provides an explanation for the angular form of this feature is that the tin lone pair is reorienting relative to the reference fluorite lattice on a simulation timescale. To quantify any lone-pair reorientation dynamics, we calculated the Sn-dipole orientational autocorrelation function ⟨μ(0) • μ(t)⟩, which describes the average change in relative orientation of the stereoactive lone pairs in time t. This autocorrelation function (Fig. ) shows a clear decay on a picosecond timescale, showing that tin lone pairs in c-BaSnF 4 undergo dynamic reorientation.