Portlandite
      Busing W, Levy H
      Journal of Chemical Physics 26 (1957) 563-568
      Neutron diffraction study of calcium hydroxide
      _cod_database_code 1008781
      _database_code_amcsd 0016656

      CELL PARAMETERS:    3.5918   3.5918   4.9063   90.000   90.000  120.000
      SPACE GROUP: P-3m1     
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:     54.816
      Density (g/cm3):      2.244
      MAX. ABS. INTENSITY / VOLUME**2:      5.205750404    
      RIR:      0.755
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                18.08        100.00        4.9063    0   0   1         2
                28.70          3.00        3.1106    1   0   0         6
                34.13          9.03        2.6271    0   1   1         6
================================================================================
       XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs
  For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.