Ca8.5NaAl6O18
      Nishi F, Takeuchi Y
      Acta Crystallographica B31 (1975) 1169-1173
      The Al6O18 rings of tetrahedra in the structure of Ca8.5NaAl6O18
      _database_code_amcsd 0017813

      CELL PARAMETERS:   10.8750  10.8590  15.1050   90.000   90.000   90.000
      SPACE GROUP: Pbca      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:   1783.774
      Density (g/cm3):      3.029
      MAX. ABS. INTENSITY / VOLUME**2:      18.51759078    
      RIR:      1.991
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                11.72          1.24        7.5525    0   0   2         2
                12.93          1.64        6.8489    1   1   1         8
                16.46          1.33        5.3864    1   1   2         8
                17.36          5.56        5.1094    0   2   1         4
                20.12          4.34        4.4128    2   0   2         4
                21.10          6.55        4.2114    1   1   3         8
                24.11          2.12        3.6919    0   2   3         4
                26.02          6.77        3.4244    2   2   2         8
                26.30          2.63        3.3891    1   1   4         8
                26.59          2.88        3.3527    3   1   1         8
                26.62          2.29        3.3489    1   3   1         8
                29.24          6.32        3.0544    2   2   3         8
                31.83          4.20        2.8115    1   1   5         8
                32.95         31.06        2.7188    4   0   0         2
                33.00         25.39        2.7148    0   4   0         2
                33.27        100.00        2.6932    2   2   4         8
                35.55          1.70        2.5253    3   3   1         8
                36.98          2.71        2.4310    4   2   0         4
                37.06          1.46        2.4257    3   3   2         8
                37.60          1.56        2.3924    1   1   6         8
                37.89          4.31        2.3748    2   2   5         8
                38.21          1.72        2.3552    2   3   4         8
                38.95          2.23        2.3122    2   4   2         8
                39.47          1.88        2.2830    3   3   3         8
                39.72          2.57        2.2695    3   1   5         8
                39.74          1.36        2.2683    1   3   5         8
                40.90          6.44        2.2064    4   0   4         4
                40.94          7.02        2.2043    0   4   4         4
                41.27          2.10        2.1876    2   4   3         8
                41.54          1.12        2.1738    4   3   0         4
                42.65          1.23        2.1198    3   3   4         8
                42.88          1.23        2.1089    1   5   1         8
                44.18          1.08        2.0498    1   5   2         8
                44.63          2.07        2.0304    1   3   6         8
                46.23          2.62        1.9638    5   1   3         8
                47.32         32.24        1.9210    4   4   0         4
                47.72          4.14        1.9057    4   4   1         8
                48.07          1.72        1.8929    2   4   5         8
                48.20         14.52        1.8881    0   0   8         2
                49.33          1.06        1.8472    4   0   6         4
                49.73          1.29        1.8336    1   1   8         8
                49.91          1.03        1.8271    1   3   7         8
                52.31          1.70        1.7488    4   2   6         8
                53.72          1.02        1.7062    2   6   1         8
                54.31          1.57        1.6892    0   4   7         4
                56.63          2.74        1.6253    2   6   3         8
                56.99          1.38        1.6158    6   1   4         8
                59.04         17.20        1.5647    6   2   4         8
                59.10         14.22        1.5632    2   6   4         8
                59.62          8.60        1.5508    4   0   8         4
                59.65          5.88        1.5501    0   4   8         4
                60.96          1.28        1.5198    3   3   8         8
                62.18          1.94        1.4929    2   6   5         8
                66.51          1.45        1.4058    2   2  10         8
                69.10          3.67        1.3594    8   0   0         2
                69.21          1.62        1.3574    0   8   0         2
                69.53          1.09        1.3519    0   8   1         4
                69.85          9.93        1.3466    4   4   8         8
                76.80          1.09        1.2412    6   6   3         8
                78.73          3.09        1.2155    8   4   0         4
                78.81          1.79        1.2144    4   8   0         4
                78.93          4.03        1.2128    6   6   4         8
                80.25          3.55        1.1962    2   2  12         8
                81.66          1.28        1.1791    6   6   5         8
                88.66          1.79        1.1032    8   0   8         4
                88.77          1.44        1.1021    0   8   8         4
================================================================================
       XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs
  For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.