AM_Cryolite_12 Formula: Al Na3 F6 Name: Cryolite Unit cell: 5.6333 5.6273 7.9619 90.0 90.0 90.0 , V=252.39 Space group: IMMM (71)

Yang H , Ghose S , Hatch D M , Physics and Chemistry of Minerals , 19 (1993) p.528-544, Ferroelastic phase transition in cryolite, Na3AlF6, a mixed, fluoride perovskite: high temperature single crystal X-ray, diffraction study and symmetry analysis of the transition mechanism, Sample: T = 900 K