Sylvite
      Walker D, Verma P K, Cranswick L M D, Jones R L, Clark S M, Buhre S
      American Mineralogist 89 (2004) 204-210
      Halite-sylvite thermoelasticity
      Sample: r57793, T = 200 C, P = 3.1 kbar, cell volume = 248.25 ang**3
      _database_code_amcsd 0003209

      CELL PARAMETERS:    6.2849   6.2849   6.2849   90.000   90.000   90.000
      SPACE GROUP: Fm3m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    248.253
      Density (g/cm3):      1.994
      MAX. ABS. INTENSITY / VOLUME**2:      35.47739829    
      RIR:      5.792
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                28.40        100.00        3.1425    2   0   0         6
                40.60         63.47        2.2220    2   2   0        12
                50.29         19.49        1.8143    2   2   2         8
                58.77          8.08        1.5712    4   0   0         6
                66.54         20.11        1.4053    4   2   0        24
                73.87         13.70        1.2829    4   2   2        24
                87.88          3.96        1.1110    4   4   0        12
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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.