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 is Na-birn
      _database_code_amcsd 0001300

      CELL PARAMETERS:    5.1740   2.8500   7.3360   90.000  103.180   90.000
      SPACE GROUP: C2/m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    105.326
      Density (g/cm3):      3.428
      MAX. ABS. INTENSITY / VOLUME**2:      67.93634863    
      RIR:      6.453
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                12.39        100.00        7.1428    0   0   1         2
                24.93         34.76        3.5714    0   0   2         2
                34.97          1.05        2.5661   -2   0   1         2
                35.64          9.92        2.5189    2   0   0         2
                36.21          1.62        2.4806    1   1   0         4
                37.00         19.68        2.4293   -1   1   1         4
                38.77          2.09        2.3229   -2   0   2         2
                39.78          4.50        2.2658    1   1   1         4
                40.60          7.06        2.2219    2   0   1         2
                41.95         11.98        2.1538   -1   1   2         4
                46.88          1.14        1.9379    1   1   2         4
                48.76          7.43        1.8676    2   0   2         2
                50.03         14.22        1.8230   -1   1   3         4
                51.15          1.73        1.7857    0   0   4         2
                55.92          2.57        1.6444   -2   0   4         2
                56.50          5.18        1.6288    1   1   3         4
                59.16          1.63        1.5616    2   0   3         2
                60.38          2.72        1.5331   -1   1   4         4
                63.00          3.83        1.4755   -3   1   1         4
                64.40          4.02        1.4468    3   1   0         4
                64.58          3.86        1.4432   -3   1   2         4
                65.50          3.01        1.4250    0   2   0         2
                66.96          1.54        1.3975    0   2   1         4
                67.61          1.23        1.3856   -2   0   5         2
                68.05          2.21        1.3777    1   1   4         4
                68.68          1.13        1.3667    3   1   1         4
                69.02          1.04        1.3607   -3   1   3         4
                71.25          2.29        1.3235    0   2   2         4
                72.56          1.52        1.3028   -1   1   5         4
                76.86          1.40        1.2403    2   2   0         4
                77.19          1.16        1.2358   -4   0   3         2
                79.99          1.26        1.1995    2   2   1         4
                81.10          1.05        1.1858   -2   0   6         2
                81.43          2.19        1.1819    1   1   5         4
                85.76          1.79        1.1329    2   2   2         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.