Ullmannite
Diffraction data computed using the structure from the paper listed below,
along with the cell parameters refined from the powder pattern for R050247
      Bayliss P
      American Mineralogist 62 (1977) 369-373
      Crystal structure refinement of arsenian ullmannite
      approximate cubic structure

      CELL PARAMETERS:   5.886000   5.886000   5.886000   90.00000   90.00000   90.00000
      SPACE GROUP: P2_13
      X-RAY WAVELENGTH:     1.541838
               2-THETA      INTENSITY    D-SPACING   H   K   L
                21.38         24.00        4.1616    1   1   0
                26.25          8.82        3.3980    1   1   1
                30.39         18.29        2.9427    2   0   0
                34.08         32.11        2.6321    2   0   1
                34.08         67.89        2.6321    2   1   0
                37.44         56.43        2.4027    2   1   1
                43.50         11.53        2.0808    2   2   0
                48.94          5.95        1.8611    3   0   1
                51.50         47.97        1.7745    3   1   1
                53.96         11.20        1.6990    2   2   2
                56.36         14.00        1.6323    3   0   2
                56.36          3.68        1.6323    3   2   0
                58.68         15.03        1.5730    3   2   1
                58.68         12.87        1.5730    3   1   2
                63.18          3.83        1.4714    4   0   0
                67.50          3.66        1.3872    4   1   1
                67.50          2.87        1.3872    3   3   0
                69.61          1.10        1.3502    3   3   1
                71.69          1.67        1.3160    4   2   0
                71.69          1.67        1.3160    4   0   2
                73.75         12.87        1.2843    4   2   1
                73.75          2.65        1.2843    4   1   2
                75.78          5.20        1.2548    3   3   2
                79.80          2.39        1.2014    4   2   2
                83.77          2.29        1.1542    5   1   0
                83.77          2.50        1.1542    4   3   1
                83.77          1.39        1.1542    4   1   3
                85.74          8.73        1.1327    5   1   1
                85.74          2.59        1.1327    3   3   3
                89.67          8.11        1.0929    4   2   3
                89.67          3.79        1.0929    4   3   2
                89.67          3.75        1.0929    5   0   2
                89.67          3.75        1.0929    5   0   2
       XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs
  For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.