Americium
      Wyckoff R W G
      Crystal Structures 1 (1963) 7-83
      Second edition. Interscience Publishers, New York, New York
      Cubic closest packed, ccp, structure
      _database_code_amcsd 0011138

      CELL PARAMETERS:    4.8940   4.8940   4.8940   90.000   90.000   90.000
      SPACE GROUP: Fm3m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    117.217
      Density (g/cm3):     13.768
      MAX. ABS. INTENSITY / VOLUME**2:      1389.658651    
      RIR:     32.866
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                31.67        100.00        2.8256    1   1   1         8
                36.73         49.45        2.4470    2   0   0         6
                52.92         31.36        1.7303    2   2   0        12
                62.99         34.23        1.4756    3   1   1        24
                66.14          9.61        1.4128    2   2   2         8
                78.11          4.07        1.2235    4   0   0         6
                86.73         11.87        1.1228    3   3   1        24
                89.57         10.89        1.0943    4   2   0        24
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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.