Quartz
      Levien L, Prewitt C T, Weidner D J
      American Mineralogist 65 (1980) 920-930
      Structure and elastic properties of quartz at pressure
      P = 55.8 kbar
      _database_code_amcsd 0000793

      CELL PARAMETERS:    4.7220   4.7220   5.2670   90.000   90.000  120.000
      SPACE GROUP: P3_221    
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    101.706
      Density (g/cm3):      2.943
      MAX. ABS. INTENSITY / VOLUME**2:      33.22174498    
      RIR:      3.676
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                21.73         20.83        4.0894    1   0   0         6
                27.62         79.07        3.2301    0   1   1         6
                27.62         20.93        3.2301    1   0   1         6
                38.12         12.29        2.3610    1   1   0         3
                40.75          3.84        2.2141    0   1   2         6
                40.75         10.00        2.2141    1   0   2         6
                41.93          5.52        2.1544    1   1   1         6
                44.30          8.08        2.0447    2   0   0         6
                52.02          8.60        1.7580    1   1   2         6
                52.09          1.32        1.7557    0   0   3         2
                57.02          3.45        1.6150    0   2   2         6
                57.02          3.50        1.6150    2   0   2         6
                57.09          2.11        1.6133    0   1   3         6
                62.64          5.28        1.4831    1   2   1         6
                62.64          5.58        1.4831    2   1   1         6
                66.35          2.70        1.4088    1   1   3         6
                70.67          6.88        1.3330    1   2   2         6
                70.73          5.12        1.3320    2   0   3         6
                71.49          7.02        1.3196    0   3   1         6
                75.91          1.27        1.2534    0   1   4         6
                75.91          3.13        1.2534    1   0   4         6
                79.11          3.12        1.2106    3   0   2         6
                83.29          3.46        1.1601    2   1   3         6
                84.19          1.95        1.1500    1   1   4         6
                85.64          1.34        1.1342    3   1   0         6
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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.