Pyroxene-ideal
      Thompson R M, Downs R T
      American Mineralogist 88 (2003) 653-666
      Model pyroxenes I: Ideal pyroxene topologies
      Pyroxene #53 based on stacking sequence ABACABACBABC
      Note: Atoms Mg, Si, and O are assigned to atomic positions just for convenience.
      _database_code_amcsd 0003075

      CELL PARAMETERS:   19.5959   6.0000   3.4641   90.000   90.000   90.000
      SPACE GROUP: Pc        
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    407.293
      Density (g/cm3):      9.821
      MAX. ABS. INTENSITY / VOLUME**2:      18.27130782    
      RIR:      0.606
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                20.10          1.19        4.4188    3   1   0         2
                27.31          4.02        3.2660    6   0   0         1
                29.78          8.54        3.0000    0   2   0         2
                29.78          4.02        3.0000    0   1   1         2
                30.14          2.05        2.9654   -1   1   1         2
                30.14          2.05        2.9654    1   1   1         2
                32.85          6.60        2.7262    3   1   1         2
                32.85          6.60        2.7262   -3   1   1         2
                40.02          1.28        2.2528   -1   2   1         2
                40.02          1.28        2.2528    1   2   1         2
                40.84         28.20        2.2094    6   2   0         2
                40.84          2.00        2.2094    6   1   1         2
                40.84          2.00        2.2094   -6   1   1         2
                40.84          6.35        2.2094   -2   2   1         2
                40.84          6.35        2.2094    2   2   1         2
                42.18         11.14        2.1423    3   2   1         2
                42.18         11.14        2.1423   -3   2   1         2
                44.00          8.29        2.0580    4   2   1         2
                44.00          8.29        2.0580   -4   2   1         2
                44.25         93.07        2.0467    9   1   0         2
                44.25          3.47        2.0467    7   1   1         2
                44.25          3.47        2.0467   -7   1   1         2
                46.25          2.47        1.9629    5   2   1         2
                46.25          2.47        1.9629   -5   2   1         2
                47.95          2.24        1.8974    8   1   1         2
                47.95          2.24        1.8974   -8   1   1         2
                48.89         16.12        1.8628    6   2   1         2
                48.89         16.12        1.8628   -6   2   1         2
                51.89          4.99        1.7621   -9   1   1         2
                51.89          4.99        1.7621    9   1   1         2
                51.89          4.67        1.7621    7   2   1         2
                51.89          4.67        1.7621   -7   2   1         2
                53.08          4.27        1.7253   -1   3   1         2
                53.08          4.27        1.7253    1   3   1         2
                53.08          2.13        1.7253   -1   0   2         1
                53.08          2.13        1.7253    1   0   2         1
                53.74          7.53        1.7056   -2   3   1         2
                53.74          7.53        1.7056    2   3   1         2
                53.74          3.77        1.7056   -2   0   2         1
                53.74          3.77        1.7056    2   0   2         1
                54.84         24.56        1.6742    3   3   1         2
                54.84         24.56        1.6742   -3   3   1         2
                54.84         12.28        1.6742    3   0   2         1
                54.84         12.28        1.6742   -3   0   2         1
                55.20          3.35        1.6641   -8   2   1         2
                55.20          3.35        1.6641    8   2   1         2
                56.06          2.36        1.6406   -2   1   2         2
                56.06          2.36        1.6406    2   1   2         2
                56.34          4.26        1.6330   12   0   0         1
                57.12          4.25        1.6126    3   1   2         2
                57.12          4.25        1.6126   -3   1   2         2
                58.24          3.36        1.5842    5   3   1         2
                58.24          3.36        1.5842   -5   3   1         2
                58.24          1.68        1.5842   -5   0   2         1
                58.24          1.68        1.5842    5   0   2         1
                58.58          3.29        1.5757    4   1   2         2
                58.58          3.29        1.5757   -4   1   2         2
                60.44          1.36        1.5317   11   1   1         2
                60.44          1.36        1.5317  -11   1   1         2
                60.44          1.02        1.5317    5   1   2         2
                60.44          1.02        1.5317   -5   1   2         2
                60.50          4.89        1.5302    6   3   1         2
                60.50          4.89        1.5302   -6   3   1         2
                60.50          2.45        1.5302    6   0   2         1
                60.50          2.45        1.5302   -6   0   2         1
                62.66          7.06        1.4827    6   1   2         2
                62.66          7.06        1.4827   -6   1   2         2
                63.12          3.28        1.4729    7   3   1         2
                63.12          3.28        1.4729   -7   3   1         2
                63.12          1.64        1.4729    7   0   2         1
                63.12          1.64        1.4729   -7   0   2         1
                65.22          2.19        1.4304    7   1   2         2
                65.22          2.19        1.4304   -7   1   2         2
                66.07          1.93        1.4142   -8   3   1         2
                66.07          1.93        1.4142    8   3   1         2
                68.12          1.67        1.3765    8   1   2         2
                68.12          1.67        1.3765   -8   1   2         2
                68.88          5.13        1.3631    6   4   0         2
                68.88          1.24        1.3631   -2   4   1         2
                68.88          1.24        1.3631    2   4   1         2
                69.33          6.66        1.3555   -9   3   1         2
                69.33          6.66        1.3555    9   3   1         2
                69.33          3.33        1.3555   -9   0   2         1
                69.33          3.33        1.3555    9   0   2         1
                69.83          2.22        1.3469   -3   4   1         2
                69.83          2.22        1.3469    3   4   1         2
                71.15          2.71        1.3252   12   2   1         2
                71.15          2.71        1.3252  -12   2   1         2
                71.15          1.73        1.3252    4   4   1         2
                71.15          1.73        1.3252   -4   4   1         2
                74.30          2.50        1.2765   15   1   0         2
                74.86          3.88        1.2684    6   4   1         2
                74.86          3.88        1.2684   -6   4   1         2
                76.75          1.17        1.2418  -11   3   1         2
                76.75          1.17        1.2418   11   3   1         2
                77.23          1.26        1.2352    7   4   1         2
                77.23          1.26        1.2352   -7   4   1         2
                77.23          1.32        1.2352    9   2   2         2
                77.23          1.32        1.2352   -9   2   2         2
                79.95          1.01        1.2000   -8   4   1         2
                79.95          1.01        1.2000    8   4   1         2
                80.91          3.41        1.1882   12   3   1         2
                80.91          3.41        1.1882  -12   3   1         2
                80.91          1.71        1.1882  -12   0   2         1
                80.91          1.71        1.1882   12   0   2         1
                82.82          1.68        1.1655  -12   1   2         2
                82.82          1.68        1.1655   12   1   2         2
                85.37          3.26        1.1371  -13   3   1         2
                85.37          3.26        1.1371   13   3   1         2
                85.37          1.63        1.1371  -13   0   2         1
                85.37          1.63        1.1371   13   0   2         1
================================================================================
       XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs
  For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.