Birnessite
      Post J E, Veblen D R
      American Mineralogist 75 (1990) 477-489
      Crystal structure determinations of synthetic sodium, magnesium and potassium
      birnessite using TEM and the Rietveld method
      Sample: Mg-birn
      _database_code_amcsd 0001301

      CELL PARAMETERS:    5.0500   2.8460   7.0540   90.000   96.630   90.000
      SPACE GROUP: C2/m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    100.704
      Density (g/cm3):      3.548
      MAX. ABS. INTENSITY / VOLUME**2:      77.94622026    
      RIR:      7.154
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                12.63        100.00        7.0068    0   0   1         2
                25.42         22.72        3.5034    0   0   2         2
                35.80          2.73        2.5081    2   0   0         2
                36.29          4.66        2.4753    1   1   0         4
                36.63          3.47        2.4530   -2   0   1         2
                37.85         16.64        2.3769   -1   1   1         4
                39.29          2.43        2.2933    1   1   1         4
                39.54         12.16        2.2794    2   0   1         2
                43.55         12.14        2.0782   -1   1   2         4
                46.09          1.66        1.9695    1   1   2         4
                46.92          4.04        1.9363    2   0   2         2
                50.21          2.85        1.8171   -2   0   3         2
                52.22          1.52        1.7517    0   0   4         2
                52.30         10.08        1.7493   -1   1   3         4
                55.62          4.43        1.6524    1   1   3         4
                56.89          3.88        1.6186    2   0   3         2
                60.91          1.45        1.5209   -2   0   4         2
                63.26          2.20        1.4699   -1   1   4         4
                64.65          5.27        1.4417    3   1   0         4
                64.70          2.65        1.4407   -3   1   1         4
                65.61          2.82        1.4230    0   2   0         2
                67.12          1.60        1.3945    0   2   1         4
                67.21          3.11        1.3930    1   1   4         4
                67.64          1.18        1.3851    3   1   1         4
                67.78          2.44        1.3825   -3   1   2         4
                71.57          1.59        1.3184    0   2   2         4
                73.51          1.44        1.2883   -2   0   5         2
                79.38          1.86        1.2071    2   2   1         4
                80.69          1.56        1.1908    1   1   5         4
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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.