Lonsdaleite
      Yeh C, Lu Z, Froyen S, Zunger A
      Physical Review B46 (1992) 10086-10097
      Zinc-blende-Wurtzite polytypism in semiconductors
      _cod_database_code 1100004
      _database_code_amcsd 0018218

      CELL PARAMETERS:    2.4900   2.4900   4.1440   90.000   90.000  120.000
      SPACE GROUP: P6_3mc    
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:     22.251
      Density (g/cm3):      3.585
      MAX. ABS. INTENSITY / VOLUME**2:      6.073925961    
      RIR:      0.552
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                41.89        100.00        2.1564    1   0   0         6
                43.69         55.73        2.0720    0   0   2         1
                47.53         53.71        1.9129    1   0   1         6
                62.13         20.07        1.4941    1   0   2         6
                76.52         12.76        1.2450    1   1   0         6
                83.02         38.90        1.1632    1   0   3         6
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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.