Periclase
      Jacobsen S D, Holl C M, Adams K A, Fischer R A, Martin E S, Bina C R, Lin J F,
      Prakapenka V B, Kubo A, Dera P
      American Mineralogist 93 (2008) 1823-1828
      Compression of single-crystal magnesium oxide to 118 GPa and a ruby pressure
      gauge for helium pressure media
      Note: P = 80.0 GPa using ruby-scale
      Note: P = 84.0 GPa using MgO-scale
      _database_code_amcsd 0004725

      CELL PARAMETERS:    3.8220   3.8220   3.8220   90.000   90.000   90.000
      SPACE GROUP: Fm3m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:     55.831
      Density (g/cm3):      4.794
      MAX. ABS. INTENSITY / VOLUME**2:      42.19172124    
      RIR:      2.865
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                40.90         13.05        2.2066    1   1   1         8
                47.58        100.00        1.9110    2   0   0         6
                69.57         46.87        1.3513    2   2   0        12
                83.98          6.48        1.1524    3   1   1        24
                88.65         13.02        1.1033    2   2   2         8
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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.