Institute of Experimental Mineralogy
                 Russian Academy of Sciences
     -------------------------------------------------
           142432, Chernogolovka, Moscow district
             A.V. Chichagov  +7(496)52-22320

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          ***      W W W - X R A Y P O L       ***
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FLUOCERITE-(CE)

2, td-fluocerite, syn, s-fluocerite

CeF(3)


Hexagonal  P 3(-)c1  Z = 6

P3(-)c1

25 .12 .17

Ref.Str.:

         Cheetham A.K., Fender B.E.F., Fuess H., Wright A.F. (1976)

         * Acta Cryst., B32, 94-97

         R: N.A.D.

                   Initial data from BDM-file 

   Lattice parameters (cub. angs.,degr.):

             a =   7.131    alpha =   90.0 
             b =   7.131    beta  =   90.0 
             c =   7.286    gamma =  120.0 

    Unit cell volume (cub. angs.) =   320.86

    Molar volume ( cub.cm/mol.) =    32.21

  Co-ordinates, thermal parameters, occupation for atomic positions:

NoP   x/a     y/b     z/c    B(j)   atom  / occupation

   1 0.6607  0.0     0.25     0.29   Ce    = 1.00
   2 0.3659  0.054   0.0824   1.17   F     = 1.00
   3 0.3333  0.6667  0.1871   1.01   F     = 1.00
   4 0.0     0.0     0.25     1.6    F     = 1.00


  Co-ordinates for all atomic positions :

   No       NoP      x/a        y/b       z/c 

     1       1     0.6607     0.0        0.25  
     2       2     0.3659     0.054      0.0824
     3       3     0.3333     0.6667     0.1871
     4       4     0.0        0.0        0.25  
     5       1     0.0        0.6607     0.25  
     6       1     0.3393     0.3393     0.25  
     7       2     0.946      0.3119     0.0824
     8       2     0.6881     0.6341     0.0824
     9       1     0.6607     0.6607     0.75  
    10       2     0.3659     0.3119     0.5824
    11       3     0.3333     0.6667     0.6871
    12       4     0.0        0.0        0.75  
    13       1     0.0        0.3393     0.75  
    14       1     0.3393     0.0        0.75  
    15       2     0.946      0.6341     0.5824
    16       2     0.6881     0.054      0.5824
    17       2     0.6341     0.946      0.9176
    18       3     0.6667     0.3333     0.8129
    19       2     0.054      0.6881     0.9176
    20       2     0.3119     0.3659     0.9176
    21       2     0.6341     0.6881     0.4176
    22       3     0.6667     0.3333     0.3129
    23       2     0.054      0.3659     0.4176
    24       2     0.3119     0.946      0.4176


X-ray density (g/cm cub.)   =      6.12

MU (1/cm) =    1560.036    Mass attenuation coefficient (cm**2/g) =    254.964

 Selected interatomic distances (cation-anion,anion-anion):

 NoP    Atom              Rad.sph.      C.N.    Distance     NoP N.
                           (angs.)               (angs.)

    1    Ce                  2.82         9
                                                 2.6207       2
                                                 2.4002       3
                                                 2.4195       4
                                                 2.4601       2
                                                 2.4447       2
                                                 2.4447       2
                                                 2.4601       2
                                                 2.4002       3
                                                 2.6208       2
    2    F                   3.192        8
                                                 2.761        3
                                                 2.7281       4
                                                 2.6769       2
                                                 2.855        3
                                                 2.719        2
                                                 2.7191       2
                                                 2.6676       3
                                                 2.5317       2
    3    F                   3.192        9
                                                 2.761        2
                                                 2.7611       2
                                                 2.7612       2
                                                 2.855        2
                                                 2.855        2
                                                 2.855        2
                                                 2.6676       2
                                                 2.6676       2
                                                 2.6675       2
    4    F                   3.192        6
                                                 2.7281       2
                                                 2.7281       2
                                                 2.7281       2
                                                 2.7281       2
                                                 2.7281       2
                                                 2.7281       2

  X-ray diffraction powder data (II),  X-Ray W.L. =   1.54056(angs.):

  No   H   K   L   Theta 2*Theta    S       LPG   MF        F          I int.
                    ( degree )                                         *100

    1   1   0   0  7.165  14.33    0.081  125.6     6       10.2       76.9
    2   0   0   2 12.207  24.414   0.137   41.86    2      278.5     6307.8
    3   1   1   0 12.476  24.953   0.14    39.98    6      139.3     4524.6
    4   1   1   1 13.917  27.834   0.156   31.74   12      208.1    16019.5
    5   1   0  -2 14.211  28.421   0.159   30.36    6        5.5        5.4
    6   1   0   2 14.211  28.421   0.159   30.36    6        4.8        4.1
    7   2   0   0 14.445  28.891   0.162   29.31    6       10.7       19.5
    8   1   1   2 17.595  35.19    0.196   19.15   12       82.0     1501.5
    9   2   0  -2 19.087  38.175   0.212   16.01    6       50.5      238.3
   10   2   0   2 19.087  38.175   0.212   16.01    6       19.8       36.6
   11   2   1   0 19.269  38.538   0.214   15.68   12        9.2       15.5
   12   2   1  -1 20.275  40.55    0.225   14.0    12       36.5      217.0
   13   2   1   1 20.275  40.55    0.225   14.0    12       14.2       33.0
   14   3   0   0 21.974  43.948   0.243   11.69    6      328.2     7341.5
   15   1   1   3 22.566  45.132   0.249   11.01   12      261.8     8798.8
   16   2   1  -2 23.075  46.149   0.254   10.47   12       17.0       35.4
   17   2   1   2 23.075  46.149   0.254   10.47   12       20.8       52.7
   18   0   0   4 25.017  50.033   0.274    8.72    2      212.5      764.5
   19   3   0  -2 25.455  50.909   0.279    8.38    6      228.1     2541.1
   20   3   0   2 25.455  50.909   0.279    8.38    6      232.2     2632.2
   21   2   2   0 25.599  51.199   0.28     8.27    6      105.9      540.2
   22   1   0  -4 26.161  52.322   0.286    7.87    6       20.2       18.7
   23   1   0   4 26.161  52.322   0.286    7.87    6       31.3       44.9
   24   2   2   1 26.412  52.824   0.289    7.7    12      178.7     2866.5
   25   3   1   0 26.726  53.451   0.292    7.5    12       15.0       19.6
   26   2   1  -3 27.239  54.478   0.297    7.18   12       16.5       22.9
   27   2   1   3 27.239  54.478   0.297    7.18   12       17.3       25.2
   28   3   1  -1 27.515  55.029   0.3      7.02   12        0.8        0.1
   29   3   1   1 27.515  55.029   0.3      7.02   12       32.0       83.7
   30   1   1   4 28.351  56.702   0.308    6.56   12       89.4      611.5
   31   2   2   2 28.753  57.506   0.312    6.35   12       77.6      445.7
   32   2   0  -4 29.405  58.81    0.319    6.04    6       19.5       13.4
   33   2   0   4 29.405  58.81    0.319    6.04    6       17.0       10.2
   34   3   1  -2 29.798  59.596   0.323    5.86   12       13.0       11.5
   35   3   1   2 29.798  59.596   0.323    5.86   12        4.0        1.1
   36   4   0   0 29.928  59.857   0.324    5.8     6       30.8       32.1
   37   2   2   3 32.411  64.821   0.348    4.87   12      204.0     2363.2
   38   2   1  -4 32.439  64.879   0.348    4.86   12        2.5        0.4
   39   2   1   4 32.439  64.879   0.348    4.86   12       16.9       16.2
   40   4   0  -2 32.811  65.622   0.352    4.74    6        4.1        0.5
   41   4   0   2 32.811  65.622   0.352    4.74    6       22.7       14.3
   42   3   2   0 32.935  65.869   0.353    4.7    12       14.2       11.1
   43   3   1  -3 33.388  66.776   0.357    4.57   12        6.9        2.6
   44   3   1   3 33.388  66.776   0.357    4.57   12        6.4        2.2
   45   3   2  -1 33.633  67.265   0.36     4.5    12       19.4       19.7
   46   3   2   1 33.633  67.265   0.36     4.5    12        9.8        5.1
   47   3   0  -4 34.379  68.758   0.367    4.3     6      191.5      918.7
   48   3   0   4 34.379  68.758   0.367    4.3     6      188.5      890.2
   49   1   1   5 34.823  69.646   0.371    4.19   12      153.9     1156.5
   50   4   1   0 34.86   69.721   0.371    4.18   12       86.2      362.2
   51   4   1  -1 35.54   71.081   0.377    4.02   12      163.1     1246.7
   52   4   1   1 35.54   71.081   0.377    4.02   12      156.4     1145.3
   53   3   2  -2 35.686  71.373   0.379    3.99   12        7.0        2.3
   54   3   2   2 35.686  71.373   0.379    3.99   12       41.0       78.1
   55   2   2   4 37.199  74.397   0.392    3.68   12       82.6      293.1
   56   4   1  -2 37.549  75.097   0.396    3.62   12       73.1      225.7
   57   4   1   2 37.549  75.097   0.396    3.62   12       76.7      248.4
   58   3   1  -4 38.12   76.24    0.401    3.52   12       19.2       15.2
   59   3   1   4 38.12   76.24    0.401    3.52   12       26.3       28.4
   60   2   1  -5 38.547  77.094   0.404    3.46   12        4.1        0.7
   61   2   1   5 38.547  77.094   0.404    3.46   12       21.8       19.2
   62   5   0   0 38.583  77.166   0.405    3.45    6       13.6        3.7
   63   3   2  -3 39.008  78.016   0.409    3.39   12       19.0       14.2
   64   3   2   3 39.008  78.016   0.409    3.39   12       19.5       15.0
   65   0   0   6 39.37   78.74    0.412    3.34    2      219.4      312.1
   66   1   0  -6 40.276  80.552   0.42     3.22    6        2.4        0.1
   67   1   0   6 40.276  80.552   0.42     3.22    6       11.8        2.6
   68   3   3   0 40.399  80.799   0.421    3.21    6      211.5      835.7
   69   4   1  -3 40.82   81.639   0.424    3.16   12      171.3     1080.6
   70   4   1   3 40.82   81.639   0.424    3.16   12      171.5     1082.0
   71   4   0  -4 40.846  81.691   0.425    3.15    6       33.7       20.8
   72   4   0   4 40.846  81.691   0.425    3.15    6       22.7        9.5
   73   3   3   1 41.047  82.094   0.426    3.13   12        1.2        0.1
   74   5   0  -2 41.187  82.373   0.427    3.12    6       47.3       40.7
   75   5   0   2 41.187  82.373   0.427    3.12    6        3.0        0.2
   76   4   2   0 41.3    82.6     0.428    3.11   12        4.1        0.6
   77   4   2  -1 41.945  83.89    0.434    3.04   12        5.5        1.1
   78   4   2   1 41.945  83.89    0.434    3.04   12       36.5       47.4
   79   1   1   6 42.075  84.15    0.435    3.03   12      108.1      412.6
   80   2   0  -6 42.97   85.94    0.442    2.96    6       23.5        9.5
   81   2   0   6 42.97   85.94    0.442    2.96    6        9.2        1.5
   82   3   3   2 42.979  85.958   0.443    2.96   12      182.4     1145.9
   83   2   2   5 43.057  86.113   0.443    2.95   12      143.0      703.0
   84   3   2  -4 43.534  87.067   0.447    2.92   12       21.4       15.5
   85   3   2   4 43.534  87.067   0.447    2.92   12       16.2        8.9
   86   4   2  -2 43.872  87.743   0.45     2.89   12        3.1        0.3
   87   4   2   2 43.872  87.743   0.45     2.89   12       13.7        6.3
   88   3   1  -5 43.949  87.899   0.45     2.89   12       21.1       14.9
   89   3   1   5 43.949  87.899   0.45     2.89   12        3.6        0.4
   90   5   1   0 43.984  87.969   0.451    2.89   12       14.3        6.9
   91   5   1  -1 44.625  89.25    0.456    2.85   12       31.0       31.9
   92   5   1   1 44.625  89.25    0.456    2.85   12        1.6        0.1


  X-ray diffraction powder data (I)...X-Ray wave length =  1.54056 (angs.):

  No   H   K   L   Theta 2*Theta    d           I int   I int.n.  I p.h.n.   H(Si)
                    ( degree )   (angstrem)     *100                         *100

    1   0   0   2  12.207  24.414  3.643       6307.8     39.4     39.5     5.6
    2   1   1   0  12.476  24.953  3.5655      4524.6     28.2     28.3     5.6
    3   1   1   1  13.917  27.834  3.20259    16019.5    100.0    100.0     5.6
    4   1   1   2  17.595  35.19   2.54815     1501.5      9.4      9.3     5.7
    5   2   0   2  19.087  38.175  2.35551      274.8      1.7      1.7     5.7
    6   2   1   1  20.275  40.55   2.22288      250.0      1.6      1.5     5.7
    7   3   0   0  21.974  43.948  2.05854     7341.5     45.8     45.1     5.7
    8   1   1   3  22.566  45.132  2.00725     8798.8     54.9     54.0     5.7
    9   0   0   4  25.017  50.033  1.8215       764.5      4.8      4.7     5.7
   10   3   0   2  25.455  50.909  1.79221     5173.3     32.3     31.6     5.8
   11   2   2   0  25.599  51.199  1.78275      540.2      3.4      3.3     5.8
   12   2   2   1  26.412  52.824  1.73167     2866.5     17.9     17.4     5.8
   13   1   1   4  28.351  56.702  1.62209      611.5      3.8      3.7     5.8
   14   2   2   2  28.753  57.506  1.60129      445.7      2.8      2.7     5.8
   15   2   2   3  32.411  64.821  1.43713     2379.7     14.9     14.2     5.9
   16   3   0   4  34.379  68.758  1.36414     1809.0     11.3     10.7     5.9
   17   1   1   5  34.823  69.646  1.34889     1156.5      7.2      6.9     5.9
   18   4   1   0  34.86   69.721  1.34763      362.2      2.3      2.1     5.9
   19   4   1   1  35.54   71.081  1.32516     2392.0     14.9     14.2     5.9
   20   2   2   4  37.199  74.397  1.27407      293.1      1.8      1.7     6.0
   21   4   1   2  37.549  75.097  1.26392      474.2      3.0      2.8     6.0
   22   0   0   6  39.37   78.74   1.21433      312.1      1.9      1.8     6.0
   23   3   3   0  40.399  80.799  1.1885       835.7      5.2      4.8     6.1
   24   4   1   3  40.82   81.639  1.17838     2192.9     13.7     12.7     6.1
   25   1   1   6  42.075  84.15   1.14949      412.6      2.6      2.4     6.1
   26   3   3   2  42.979  85.958  1.12989     1156.8      7.2      6.6     6.1
   27   2   2   5  43.057  86.113  1.12825      703.0      4.4      4.0     6.1

Reference:
Chichagov A.V. et al.
Information-Calculating System on Crystal Structure Data of Minerals
(MINCRYST)
- Kristallographiya, v.35, n.3, 1990, p.610-616 (in Russian)