(NH4)3H(SO4)2
      Friese K, Aroyo M I, Schwalowsky I, Adiwidjaja G, Bismayer U
      Journal of Solid State Chemistry 165 (2002) 136-147
      The disordered high-temperature structure of (NH4)3H(SO4)2 and its relationship
      to the room-temperature phase
      Locality: synthetic
      Sample: T = 420 K
      Note: high-temperature polymorph of letovicite
      _database_code_amcsd 0014023

      CELL PARAMETERS:    5.9039   5.9039  22.5360   90.000   90.000  120.000
      SPACE GROUP: R-3m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    680.276
      Density (g/cm3):      1.810
      MAX. ABS. INTENSITY / VOLUME**2:      7.681783872    
      RIR:      1.382
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                11.78          1.34        7.5120    0   0   3         2
                17.79        100.00        4.9862    1   0   1         6
                19.06         29.35        4.6560    0   1   2         6
                23.50         32.97        3.7862    1   0   4         6
                23.69         25.66        3.7560    0   0   6         2
                26.36         86.96        3.3810    0   1   5         6
                30.28         59.71        2.9520    1   1   0         6
                32.59          6.08        2.7474    1   1   3        12
                32.88          7.38        2.7243    1   0   7         6
                35.33          3.08        2.5402    0   2   1         6
                35.86          5.48        2.5040    0   0   9         2
                36.02          9.15        2.4931    2   0   2         6
                36.41          7.39        2.4673    0   1   8         6
                38.68          2.40        2.3280    0   2   4         6
                40.57         22.94        2.2237    2   0   5         6
                43.91          4.52        2.0622    1   0  10         6
                47.75          1.18        1.9047    1   2   2        12
                48.47          2.94        1.8780    0   0  12         2
                49.89          5.42        1.8280    2   1   4        12
                51.45          2.43        1.7761    1   2   5        12
                53.79          2.55        1.7043    3   0   0         6
                55.27          1.87        1.6621    3   0   3         6
                56.01          2.67        1.6417    1   0  13         6
                57.66          2.46        1.5987    2   0  11         6
                58.23          1.74        1.5845    1   1  12        12
                62.97          3.85        1.4760    2   2   0         6
                63.41          3.69        1.4670    2   1  10        12
                68.28          1.19        1.3737    2   2   6        12
                69.49          2.29        1.3527    3   1   5        12
                70.31          1.70        1.3390    1   1  15        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.