Valentinite
Diffraction data computed using the structure from the paper listed below,
along with the cell parameters refined from single crystal data of R060516
      Buerger M J
      American Mineralogist 21 (1936) 206-207
      The crystal structure of valentinite

      CELL PARAMETERS:   4.9152 12.7500  5.4150   90.000   90.000   90.000
      SPACE GROUP: Pccn      

           ATOM        X         Y         Z     OCCUPANCY  ISO(B)
            Sb     0.12150   0.20700   0.17500     1.000     1.000
            O      0.25000   0.25000  -0.07500     1.000     1.000
            O     -0.11000   0.15600   0.17500     1.000     1.000

            X-RAY WAVELENGTH:     1.541838
            BOUNDS ON TWO THETA:    5.0  90.0
            LIMITS IMPOSED ON THE INDICES ARE:  +/-  4 +/- 11 +/-  4
            MAX. ABS. INTENSITY / VOLUME**2:      341.6761353    
            The INTENSITY cut off value is   1.00

               2-THETA      INTENSITY    D-SPACING   H   K   L
                13.89        100.00        6.3750    0   2   0
                19.35         41.16        4.5862    1   1   0
                25.45          1.29        3.4997    1   1   1
                27.75         12.20        3.2149    1   3   0
                27.99          3.57        3.1875    0   4   0
                28.23         12.96        3.1607    1   2   1
                32.39          4.06        2.7644    1   3   1
                33.09          4.62        2.7075    0   0   2
                33.85         14.61        2.6484    0   1   2
                36.04          4.46        2.4921    0   2   2
                37.51         13.03        2.3979    1   4   1
                37.94          2.97        2.3715    1   0   2
                38.62          2.87        2.3315    1   1   2
                39.46          3.25        2.2835    0   3   2
                39.83          1.22        2.2635    1   5   0
                40.59          4.11        2.2227    1   2   2
                43.33          2.26        2.0884    1   5   1
                43.71          1.30        2.0709    1   3   2
                45.82          5.07        1.9802    2   3   1
                47.80          1.03        1.9027    1   4   2
                49.68          5.04        1.8351    1   6   1
                49.78          1.76        1.8316    2   4   1
                54.56          7.14        1.6820    2   5   1
                56.64          1.49        1.6250    3   1   0
                58.66          2.78        1.5739    1   3   3
                60.04          1.59        1.5410    2   6   1
                63.75          1.23        1.4599    1   8   1
                66.15          4.32        1.4127    2   7   1
                66.22          2.57        1.4112    1   5   3
                66.44          1.51        1.4071    3   4   1
                68.54          1.29        1.3690    3   2   2
                69.87          2.30        1.3462    0   1   4
                71.25          2.53        1.3235    2   4   3
                74.16          1.19        1.2786    1   2   4
                75.32          1.06        1.2618    3   6   1
                76.84          1.16        1.2406    1   7   3
                79.91          2.83        1.2004    2   6   3
                80.19          1.13        1.1970    2   9   1
                87.52          1.58        1.1147    4   1   2
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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.