Silicon
      McMahon M I, Nelmes R J
      Physical Review B47 (1993) 8337-8340
      New high-pressure phase of Si
      Locality: synthetic
      Sample: structure exists between 13 GPa to 18 GPa
      Note: intermediate structure between those of Si II and Si V
      _database_code_amcsd 0015170

      CELL PARAMETERS:    4.7370   4.5020   2.5500   90.000   90.000   90.000
      SPACE GROUP: Imma      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:     54.381
      Density (g/cm3):      3.430
      MAX. ABS. INTENSITY / VOLUME**2:      21.40583078    
      RIR:      2.032
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                37.99         70.21        2.3685    2   0   0         2
                40.06         59.70        2.2510    0   2   0         2
                40.16         14.55        2.2453    1   0   1         4
                40.66        100.00        2.2188    0   1   1         4
                56.39         40.67        1.6317    2   2   0         4
                56.86         69.46        1.6193    2   1   1         8
                58.02          9.12        1.5897    1   2   1         8
                70.09          2.49        1.3425    3   0   1         4
                73.18         15.60        1.2933    0   3   1         4
                74.41          4.81        1.2750    0   0   2         2
                80.96         11.43        1.1876    1   1   2         8
                81.23          6.57        1.1842    4   0   0         2
                83.92          2.96        1.1530    3   2   1         8
                85.55         20.13        1.1351    2   3   1         8
                86.46          5.59        1.1255    0   4   0         2
                86.74          6.31        1.1227    2   0   2         4
                88.04          6.10        1.1094    0   2   2         4
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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.