As3 Sn4
      Haegg G, Hybinette A
      Philosophical Magazine 20 (1935) 913-929
      X-ray studies on the systems tin-antimony and tin-arsenic
      _cod_database_code 1010003
      _database_code_amcsd 0016939

      CELL PARAMETERS:   12.2300  12.2300  12.2300   19.220   19.220   19.220
      SPACE GROUP: R-3m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    173.290
      Density (g/cm3):      6.703
      MAX. ABS. INTENSITY / VOLUME**2:      306.0189059    
      RIR:     14.866
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                22.22          1.28        4.0002    3   3   3         2
                25.67          2.64        3.4700    1   1   0         6
                28.11          2.06        3.1742    2   2   1         6
                30.68        100.00        2.9140    3   2   2         6
                44.37         33.99        2.0417    0  -1   1         6
                54.91         17.01        1.6721    3   3   1         6
                81.69          4.52        1.1788    1  -2   1         6
================================================================================
       XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs
  For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.