K2O2
      Wyckoff R W G
      Crystal Structures 1 (1963) 85-237
      Second edition. Interscience Publishers, New York, New York
      Potassium peroxide
      _database_code_amcsd 0011667

      CELL PARAMETERS:    6.7360   7.0010   6.4790   90.000   90.000   90.000
      SPACE GROUP: Cmca      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    305.541
      Density (g/cm3):      2.395
      MAX. ABS. INTENSITY / VOLUME**2:      13.35099418    
      RIR:      1.815
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                22.89         53.69        3.8847    1   1   1         8
                25.45          4.80        3.5005    0   2   0         2
                26.46         25.82        3.3680    2   0   0         2
                27.53         35.81        3.2395    0   0   2         2
                28.99         68.89        3.0797    0   2   1         4
                33.25          4.29        2.6945    1   1   2         8
                37.04         21.30        2.4270    2   2   0         4
                37.84         16.08        2.3776    0   2   2         4
                38.56         81.21        2.3348    2   0   2         4
                39.66        100.00        2.2728    2   2   1         8
                44.63          5.90        2.0304    3   1   1         8
                46.77          4.60        1.9424    2   2   2         8
                49.60         30.75        1.8380    0   2   3         4
                50.04          3.28        1.8229    1   3   2         8
                52.27          6.20        1.7502    0   4   0         2
                54.29         11.28        1.6897    0   4   1         4
                54.49         13.37        1.6840    4   0   0         2
                56.84          5.45        1.6198    0   0   4         2
                57.09          7.67        1.6134    2   2   3         8
                59.52          1.62        1.5531    2   4   0         4
                60.08          2.18        1.5399    0   4   2         4
                61.39          7.20        1.5103    2   4   1         8
                62.12          4.53        1.4942    4   0   2         4
                62.90          9.20        1.4775    4   2   1         8
                63.26          1.48        1.4700    0   2   4         4
                63.76          7.87        1.4597    2   0   4         4
                64.36          1.08        1.4475    3   3   2         8
                66.80          7.59        1.4004    2   4   2         8
                68.25          3.25        1.3742    4   2   2         8
                69.08          1.29        1.3598    0   4   3         4
                69.81          1.74        1.3473    2   2   4         8
                72.39          1.17        1.3054    1   3   4         8
                75.38          8.34        1.2609    2   4   3         8
                76.76         10.45        1.2416    4   2   3         8
                78.75          1.28        1.2152    0   2   5         4
                78.88          2.34        1.2135    4   4   0         4
                80.53          4.72        1.1928    4   4   1         8
                80.86          1.14        1.1888    0   4   4         4
                82.66          2.59        1.1674    4   0   4         4
                84.82          7.05        1.1431    2   2   5         8
                85.44          1.22        1.1364    4   4   2         8
                86.90          2.03        1.1210    2   4   4         8
                88.73          3.80        1.1025    2   6   0         4
                89.21          3.13        1.0978    0   6   2         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.