Ercitite
      Cooper M A, Hawthorne F C, Cerny P
      The Canadian Mineralogist 47 (2009) 173-180
      The crystal structure of ercitite, Na2(H2O)4[Mn3+2(OH)2(PO4)2],
      and its relation to bermanite, Mn2+(H2O)4[Mn3+2(OH)2(PO4)2]
      Locality: Tanco granitic pegmatite, Bernic Lake, southeastern Manitoba, Canada
      _database_code_amcsd 0006278

      CELL PARAMETERS:    6.2499   8.7479  19.9554   90.000   90.000   90.000
      SPACE GROUP: Cmca      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:   1091.032
      Density (g/cm3):      2.755
      MAX. ABS. INTENSITY / VOLUME**2:      26.76807230    
      RIR:      3.164
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                 8.86        100.00        9.9777    0   0   2         2
                17.78          3.46        4.9889    0   0   4         2
                18.00         17.13        4.9279    1   1   1         8
                20.30          1.75        4.3740    0   2   0         2
                20.79          3.03        4.2725    0   2   1         4
                22.19         11.68        4.0059    0   2   2         4
                26.81          1.53        3.3259    0   0   6         2
                27.11         25.42        3.2889    0   2   4         4
                28.43         12.24        3.1396    1   1   5         8
                29.96          3.26        2.9821    2   0   2         4
                33.85         20.44        2.6483    2   0   4         4
                33.86         10.02        2.6475    0   2   6         4
                34.23          6.18        2.6196    1   3   1         8
                35.13          3.56        2.5544    1   3   2         8
                35.30         13.89        2.5427    2   2   0         4
                35.59          2.84        2.5223    2   2   1         8
                36.12          5.73        2.4867    1   1   7         8
                36.47          7.80        2.4639    2   2   2         8
                36.59          4.96        2.4558    1   3   3         8
                37.66          5.68        2.3883    0   2   7         4
                37.88          1.62        2.3751    2   2   3         8
                39.79          4.04        2.2654    2   2   4         8
                41.54          1.31        2.1740    0   4   1         4
                41.68          5.68        2.1668    0   2   8         4
                42.14          5.58        2.1445    2   2   5         8
                43.56          1.16        2.0776    0   4   3         4
                44.87          1.78        2.0200    2   2   6         8
                45.68          1.09        1.9861    3   1   2         8
                46.59          3.87        1.9495    2   0   8         4
                46.88          1.21        1.9380    1   3   7         8
                49.91          2.46        1.8273    0   4   6         4
                51.31          2.61        1.7806    2   2   8         8
                51.84          4.01        1.7636    2   4   2         8
                54.31          2.43        1.6890    3   3   1         8
                54.41          7.04        1.6863    2   4   4         8
                54.56          1.54        1.6819    2   0  10         4
                55.24          3.72        1.6630    0   0  12         2
                55.91          2.41        1.6444    0   4   8         4
                56.28          1.91        1.6346    2   4   5         8
                58.51          6.72        1.5774    2   4   6         8
                58.82          4.72        1.5698    2   2  10         8
                59.13          5.16        1.5625    4   0   0         2
                59.92          1.11        1.5437    4   0   2         4
                61.09          1.17        1.5170    2   4   7         8
                63.06          2.12        1.4741    0   4  10         4
                63.98          1.57        1.4552    2   4   8         8
                66.22          2.52        1.4113    4   2   4         8
                67.27          2.75        1.3917    2   2  12         8
                69.34          1.16        1.3552    0   2  14         4
                69.91          1.94        1.3456    4   2   6         8
                71.39          1.33        1.3213    2   6   0         4
                72.11          1.66        1.3098    2   6   2         8
                72.95          1.06        1.2968    2   0  14         4
                73.01          1.13        1.2959    2   6   3         8
                74.93          1.19        1.2673    4   2   8         8
                83.45          1.53        1.1584    2   0  16         4
                85.22          1.08        1.1387    4   0  12         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.