Villiaumite
      Bragg W
      Nature 105 (1920) 646-648
      Crystal structure of Na F
      _cod_database_code 1011282
      _database_code_amcsd 0018133

      CELL PARAMETERS:    4.7800   4.7800   4.7800   90.000   90.000   90.000
      SPACE GROUP: Fm3m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    109.215
      Density (g/cm3):      2.553
      MAX. ABS. INTENSITY / VOLUME**2:      25.90114477    
      RIR:      3.303
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                32.44          1.79        2.7597    1   1   1         8
                37.64        100.00        2.3900    2   0   0         6
                54.28         52.28        1.6900    2   2   0        12
                67.93         13.48        1.3799    2   2   2         8
                80.35          4.95        1.1950    4   0   0         6
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       XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs
  For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.