Virgilite
      Muller G, Paulus H, Stiefel J
      Neues Jahrbuch fur Mineralogie, Monatshefte 1990 (1990) 493-503
      Synthesis and structure of beta-quartz type
      Na0.5H0.5AlSi206 as compared to LiAlSi206
      Locality: synthetic
      Note: stuffed beta-quartz type structure
      _database_code_amcsd 0014849

      CELL PARAMETERS:    5.2260   5.2260   5.4650   90.000   90.000  120.000
      SPACE GROUP: P6_222    
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    129.259
      Density (g/cm3):      2.390
      MAX. ABS. INTENSITY / VOLUME**2:      33.58425810    
      RIR:      4.575
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                19.61         11.54        4.5258    1   0   0         6
                25.55        100.00        3.4857    1   0   1        12
                34.32          3.98        2.6130    1   1   0         6
                38.48          1.62        2.3392    1   0   2        12
                39.84          3.86        2.2629    2   0   0         6
                43.27          2.88        2.0908    2   0   1        12
                48.19         18.14        1.8885    1   1   2        12
                52.51          1.22        1.7429    2   0   2        12
                56.36          8.20        1.6325    2   1   1        12
                61.46          1.10        1.5086    3   0   0         6
                64.24          3.46        1.4499    2   1   2        12
                65.81          7.88        1.4190    2   0   3        12
                71.43          2.55        1.3207    3   0   2        12
                72.32          2.87        1.3065    2   2   0         6
                76.37          2.23        1.2470    2   1   3        12
                78.12          4.12        1.2234    3   1   1        12
                79.10          2.52        1.2107    1   1   4        12
                85.04          1.27        1.1406    3   1   2        12
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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.