Pyroxene-ideal
      Thompson R M, Downs R T
      American Mineralogist 89 (2004) 614-628
      Model pyroxenes II: Structural variation as a function of tetrahedral rotation
      model spodumene after Cameron et al. (1973)
      with O3-O3-O3 angle = 189.5 and model oxygen radius = 1.263
      _database_code_amcsd 0003487

      CELL PARAMETERS:    9.5700   8.7170   5.0330   90.000  112.100   90.000
      SPACE GROUP: C2/c      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    389.014
      Density (g/cm3):      3.177
      MAX. ABS. INTENSITY / VOLUME**2:      11.16910088    
      RIR:      1.145
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                20.03          9.95        4.4334    2   0   0         2
                20.38         54.57        4.3585    0   2   0         2
                20.58          4.65        4.3166   -1   1   1         4
                26.75         33.31        3.3322    1   1   1         4
                28.02         34.96        3.1842    0   2   1         4
                28.72          3.22        3.1081    2   2   0         4
                30.05        100.00        2.9734   -2   2   1         4
                30.85          9.19        2.8985   -3   1   1         4
                31.97         54.21        2.7991    3   1   0         4
                32.42          4.84        2.7612    1   3   0         4
                36.16          8.47        2.4843   -2   0   2         2
                37.45          1.58        2.4013   -1   1   2         4
                38.62         36.84        2.3316    0   0   2         2
                38.83          7.03        2.3193    2   2   1         4
                40.70          7.43        2.2167    4   0   0         2
                41.86          2.65        2.1583   -2   2   2         4
                42.83         12.92        2.1114   -3   3   1         4
                43.22          2.71        2.0933    3   1   1         4
                43.33          1.62        2.0881   -4   2   1         4
                43.68          2.46        2.0721    3   3   0         4
                44.56          4.15        2.0333   -4   0   2         2
                44.98          4.24        2.0153    1   1   2         4
                45.97          6.01        1.9743    0   4   1         4
                47.32         25.75        1.9208   -2   4   1         4
                48.71          4.36        1.8694   -5   1   1         4
                49.46          3.50        1.8427   -4   2   2         4
                50.63          1.70        1.8030    2   0   2         2
                50.63          1.14        1.8028   -3   3   2         4
                52.67          1.20        1.7378    5   1   0         4
                53.57          3.32        1.7106    1   5   0         4
                53.75          2.31        1.7054    2   4   1         4
                54.40          1.14        1.6867    1   3   2         4
                55.12          1.95        1.6661    2   2   2         4
                56.14          2.20        1.6383   -2   4   2         4
                56.33          5.73        1.6332    4   2   1         4
                57.67         16.73        1.5984   -5   3   1         4
                57.92          1.37        1.5921    0   4   2         4
                58.83          2.68        1.5696    1   5   1         4
                59.02         14.67        1.5652   -2   2   3         4
                59.48          3.69        1.5540    4   4   0         4
                60.01          9.90        1.5416    3   1   2         4
                60.22          2.02        1.5367   -6   0   2         2
                61.78          1.28        1.5016    3   5   0         4
                62.47          1.56        1.4867   -4   4   2         4
                62.89          5.24        1.4778    6   0   0         2
                63.97          1.84        1.4555   -5   1   3         4
                64.10          8.32        1.4528    0   6   0         2
                64.27          1.02        1.4493   -6   2   2         4
                64.79          4.04        1.4389   -3   3   3         4
                65.26          2.67        1.4296   -1   5   2         4
                65.64          2.74        1.4223    1   1   3         4
                67.42          1.70        1.3891   -3   5   2         4
                68.49          2.61        1.3699    4   4   1         4
                70.87          9.22        1.3297   -7   1   2         4
                70.91          7.95        1.3291   -2   4   3         4
                71.43         11.49        1.3206    5   3   1         4
                71.71          1.31        1.3161   -5   3   3         4
                73.31          2.22        1.2914    1   3   3         4
                73.47          1.60        1.2889   -5   5   1         4
                75.86          5.04        1.2541   -2   6   2         4
                75.90          1.65        1.2535    7   1   0         4
                76.23          1.51        1.2490   -2   0   4         2
                76.65          1.39        1.2432    5   5   0         4
                76.73          5.77        1.2421   -4   0   4         2
                77.40          7.96        1.2331    0   6   2         4
                77.57          2.42        1.2307   -7   3   1         4
                79.56          2.90        1.2048   -1   1   4         4
                80.13          1.30        1.1977    5   1   2         4
                80.38          1.73        1.1946   -4   2   4         4
                81.41          1.64        1.1821   -4   6   2         4
                82.85          2.25        1.1651    3   5   2         4
                85.37          1.13        1.1371   -7   3   3         4
                85.92          2.35        1.1313    2   6   2         4
                87.88          1.35        1.1110    1   5   3         4
================================================================================
       XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs
  For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.