Ringwoodite
      Kudoh Y, Kuribayashi T, Mizobata H, Ohtami E
      Physics and Chemistry of Minerals 27 (2000) 474-479
      Structure and cation disorder of hydrous ringwoodite,
      gamma-Mg1.89Si0.98H0.30O4
      _database_code_amcsd 0008430

      CELL PARAMETERS:    8.0693   8.0693   8.0693   90.000   90.000   90.000
      SPACE GROUP: Fd3m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    525.421
      Density (g/cm3):      3.354
      MAX. ABS. INTENSITY / VOLUME**2:      21.17521219    
      RIR:      2.056
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                31.35         31.74        2.8529    2   2   0        12
                36.95        100.00        2.4330    3   1   1        24
                38.65          1.52        2.3294    2   2   2         8
                44.93         39.95        2.0173    4   0   0         6
                49.22          1.99        1.8512    3   3   1        24
                55.81         10.26        1.6471    4   2   2        24
                59.53         15.23        1.5529    5   1   1        24
                59.53          9.96        1.5529    3   3   3         8
                65.43         59.16        1.4265    4   4   0        12
                74.35          4.01        1.2759    6   2   0        24
                77.58          9.01        1.2306    5   3   3        24
                82.89          4.25        1.1647    4   4   4         8
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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.