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The full array of structure-related experimental data for XeF6 is considered simultaneously. Electron diffraction, infrared, Raman and ultraviolet spectra, electric field deflection of molecular beam, and calorimetrically determined entropy data are all found to be consistent with a structural model involving substantial distortion in the T," bending mode from octahedral symmetry and a pseudorotation in two dimensions of this distortion. Several other vibration frequencies are assigned, and the mean value of three unobserved frequencies is determined from the entropy. No quantitative value could be given for the potential restricting pseudorotation, but various arguments agree in indicating that it is small. There is no reason to question previous proposals that this peculiar structure arises from a pseudo-Jahn-Teller effect associated with the relatively low energy of excitation of a xenon 5 s electron to the 5 p level.