Villiaumite
Wyckoff R W G
Crystal Structures 1 (1963) 85-237
Second edition. Interscience Publishers, New York, New York
rocksalt structure
_database_code_amcsd 0011357
4.620 4.620 4.620 90 90 90 Fm3m
atom  x  y  z
Na    0  0  0
F    .5 .5 .5