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 = 53.0 GPa using ruby-scale
      Note: P = 55.1 GPa using MgO-scale
      _database_code_amcsd 0004695

      CELL PARAMETERS:    3.9130   3.9130   3.9130   90.000   90.000   90.000
      SPACE GROUP: Fm3m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:     59.914
      Density (g/cm3):      4.468
      MAX. ABS. INTENSITY / VOLUME**2:      40.02933465    
      RIR:      2.917
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                39.90         12.50        2.2592    1   1   1         8
                46.41        100.00        1.9565    2   0   0         6
                67.73         47.67        1.3835    2   2   0        12
                81.60          6.43        1.1798    3   1   1        24
                86.08         13.08        1.1296    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.