AM_Villiaumite_1 Formula: Na F Name: Villiaumite Unit cell: 4.64 4.64 4.64 90.0 90.0 90.0 , V=99.90 Space group: FM3M (225)

Deshpande V T , Acta Crystallographica , 14 (1961) p.794-794, Thermal expansion of sodium fluoride and sodium bromide, Note: T = 68.1 C, rocksalt structure