Ahrensite
      Yamanaka T
      Physics and Chemistry of Minerals 13 (1986) 227-232
      Crystal structures of Ni2SiO4 and Fe2SiO4 as a function of
      temperature and heating duration
      Sample: T = 700 C
      Locality: synthetic
      _database_code_amcsd 0007408

      CELL PARAMETERS:    8.3398   8.3398   8.3398   90.000   90.000   90.000
      SPACE GROUP: Fd3m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    580.052
      Density (g/cm3):      4.666
      MAX. ABS. INTENSITY / VOLUME**2:      55.10611440    
      RIR:      3.845
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                18.43         30.88        4.8150    1   1   1         8
                30.31         11.01        2.9486    2   2   0        12
                35.71        100.00        2.5145    3   1   1        24
                37.35         13.28        2.4075    2   2   2         8
                43.40         44.42        2.0849    4   0   0         6
                47.52         13.09        1.9133    3   3   1        24
                53.85          2.76        1.7024    4   2   2        24
                57.41          8.13        1.6050    3   3   3         8
                57.41         12.87        1.6050    5   1   1        24
                63.06         36.43        1.4743    4   4   0        12
                66.31          3.48        1.4097    5   3   1        48
                74.62          6.12        1.2718    5   3   3        24
                75.64          4.75        1.2573    6   2   2        24
                79.65          4.07        1.2037    4   4   4         8
                82.62          1.22        1.1678    7   1   1        24
                87.54          1.05        1.1145    6   4   2        48
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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.