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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FORSTERITE

53, t-olivine, Co-Mg-analogue

Co(2)SiO(4)


Orthorhombic  P bnm  Z = 4

R =0.0493

4 .11 .1997

Ref.Str.:

         Muller-Sommer M., Hocd R., Kirfel A. (1997)

         * Phys. Chem. Minerals, 24, 17-23

Reserv:

         In original - olivine[39].     D.T.N.

                   Initial data from BDM-file 

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

             a =   4.7814   alpha =   90.0 
             b =  10.2924   beta  =   90.0 
             c =   6.0007   gamma =   90.0 

    Unit cell volume (cub. angs.) =   295.31

    Molar volume ( cub.cm/mol.) =    44.47

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

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

   1 0.0     0.0     0.0      0.0    Co    = 0.93, Mg    = 0.07
   2 0.9891  0.2767  0.25     0.0    Co    = 0.82, Mg    = 0.18
   3 0.4318  0.0949  0.25     0.0    Si    = 1.00
   4 0.7534  0.0873  0.25     0.0    O     = 1.00
   5 0.2223  0.45    0.25     0.0    O     = 1.00
   6 0.2929  0.1641  0.0384   0.0    O     = 1.00


  Co-ordinates for all atomic positions :

   No       NoP      x/a        y/b       z/c 

     1       1     0.0        0.0        0.0   
     2       2     0.9891     0.2767     0.25  
     3       3     0.4318     0.0949     0.25  
     4       4     0.7534     0.0873     0.25  
     5       5     0.2223     0.45       0.25  
     6       6     0.2929     0.1641     0.0384
     7       2     0.0109     0.7233     0.75  
     8       3     0.5682     0.9051     0.75  
     9       4     0.2466     0.9127     0.75  
    10       5     0.7777     0.55       0.75  
    11       6     0.7071     0.8359     0.9616
    12       1     0.0        0.0        0.5   
    13       6     0.7071     0.8359     0.5384
    14       6     0.2929     0.1641     0.4616
    15       1     0.5        0.5        0.0   
    16       2     0.5109     0.7767     0.25  
    17       3     0.0682     0.5949     0.25  
    18       4     0.7466     0.5873     0.25  
    19       5     0.2777     0.95       0.25  
    20       6     0.2071     0.6641     0.0384
    21       2     0.4891     0.2233     0.75  
    22       3     0.9318     0.4051     0.75  
    23       4     0.2534     0.4127     0.75  
    24       5     0.7223     0.05       0.75  
    25       6     0.7929     0.3359     0.9616
    26       1     0.5        0.5        0.5   
    27       6     0.7929     0.3359     0.5384
    28       6     0.2071     0.6641     0.4616


X-ray density (g/cm cub.)   =      4.53

MU (1/cm) =     234.351    Mass attenuation coefficient (cm**2/g) =     51.778

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

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

    1   Co   ,Mg             2.568        6
                                                 2.1091       4
                                                 2.2061       6
                                                 2.1091       4
                                                 2.2061       6
                                                 2.0684       5
                                                 2.0684       5
    2   Co   ,Mg             2.568        6
                                                 2.2517       4
                                                 2.1035       5
                                                 2.2506       6
                                                 2.2506       6
                                                 2.0607       6
                                                 2.0607       6
    3    Si                  2.1          4
                                                 1.5397       4
                                                 1.6002       6
                                                 1.6002       6
                                                 1.6635       5
    4    O                   3.264       12
                                                 2.9818       6
                                                 2.6618       6
                                                 3.1208       6
                                                 3.1208       6
                                                 2.9818       6
                                                 2.6618       6
                                                 2.8778       5
                                                 2.6778       5
                                                 3.0285       5
                                                 3.0285       5
                                                 3.0948       6
                                                 3.0948       6
    5    O                   3.264       10
                                                 3.2226       6
                                                 3.2226       6
                                                 2.8778       4
                                                 2.6778       4
                                                 2.5443       6
                                                 3.0285       4
                                                 3.0285       4
                                                 2.9308       6
                                                 2.9308       6
                                                 2.5443       6
    6    O                   3.264       10
                                                 2.6618       4
                                                 2.9818       4
                                                 3.2226       5
                                                 3.1208       4
                                                 2.5395       6
                                                 2.5443       5
                                                 3.0948       4
                                                 2.9308       5
                                                 3.0091       6
                                                 3.0091       6

  X-ray diffraction powder data (II),  X-Ray W.L. =   1.78892(angs.):

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

    1   0   2   0 10.009  20.019   0.097   63.29    2       39.1      222.2
    2   1   1   0 11.904  23.808   0.115   44.12    4       31.6      202.4
    3   0   2   1 13.237  26.473   0.128   35.29    4       34.1      187.7
    4   1   0   1 13.839  27.678   0.134   32.12    4       24.9       91.1
    5   1   1   1 14.744  29.487   0.142   28.06    8       57.8      860.2
    6   1   2   0 14.795  29.589   0.143   27.86    4       24.9       79.1
    7   1   2   1 17.198  34.396   0.165   20.13    8       14.6       39.3
    8   0   0   2 17.345  34.689   0.167   19.76    2       41.0       76.0
    9   1   3   0 18.716  37.433   0.179   16.72    4      139.5     1493.3
   10   0   2   2 20.187  40.374   0.193   14.14    4       91.2      539.3
   11   0   4   0 20.342  40.684   0.194   13.9     2       81.2      210.4
   12   1   3   1 20.721  41.442   0.198   13.34    8       97.0     1151.8
   13   1   1   2 21.255  42.51    0.203   12.6     8      120.1     1666.1
   14   2   0   0 21.971  43.943   0.209   11.7     2       98.2      258.9
   15   0   4   1 22.224  44.448   0.211   11.4     4       60.3      189.8
   16   2   1   0 22.588  45.176   0.215   10.99    4       43.0       93.3
   17   1   2   2 23.112  46.224   0.219   10.43    8       47.0      211.2
   18   1   4   0 23.251  46.502   0.221   10.29    4       63.2      188.8
   19   2   1   1 24.331  48.662   0.23     9.29    8       31.2       83.1
   20   2   2   0 24.365  48.729   0.231    9.26    4       10.7        4.8
   21   1   4   1 24.959  49.917   0.236    8.76    8        2.0        0.3
   22   1   3   2 25.976  51.952   0.245    8.0     8       45.8      153.9
   23   2   2   1 26.018  52.035   0.245    7.97    8       14.7       15.7
   24   2   3   0 27.131  54.261   0.255    7.25    4       14.3        6.8
   25   0   4   2 27.255  54.509   0.256    7.17    4       32.3       34.3
   26   1   5   0 28.235  56.469   0.264    6.62    4       49.2       73.3
   27   2   0   2 28.58   57.161   0.267    6.44    4        9.2        2.5
   28   2   3   1 28.67   57.34    0.268    6.39    8        2.1        0.3
   29   0   2   3 28.67   57.341   0.268    6.39    4        5.7        1.0
   30   1   0   3 28.995  57.99    0.271    6.23    4       13.5        5.2
   31   2   1   2 29.092  58.185   0.272    6.19    8        8.0        3.7
   32   1   1   3 29.502  59.005   0.275    5.99    8       54.2      161.5
   33   1   4   2 29.649  59.297   0.277    5.93    8        1.1        0.1
   34   1   5   1 29.736  59.473   0.277    5.89    8       44.3      105.9
   35   2   2   2 30.596  61.193   0.285    5.53    8      156.1     1235.5
   36   2   4   0 30.711  61.422   0.285    5.48    4      125.8      397.5
   37   1   2   3 30.994  61.988   0.288    5.37    8       25.4       31.7
   38   0   6   0 31.428  62.856   0.291    5.21    2       16.3        3.2
   39   2   4   1 32.142  64.283   0.297    4.96    8       61.0      169.4
   40   0   6   1 32.841  65.683   0.303    4.73    4       85.6      159.1
   41   2   3   2 33.012  66.025   0.305    4.68    8       12.2        6.4
   42   1   3   3 33.394  66.788   0.308    4.57    8       80.6      272.5
   43   1   6   0 33.64   67.28    0.31     4.5     4       17.5        6.4
   44   1   5   2 33.999  67.998   0.313    4.4     8       80.6      262.1
   45   0   4   3 34.499  68.999   0.317    4.27    4       75.2      110.7
   46   3   1   0 34.604  69.208   0.317    4.24    4       66.5       86.0
   47   2   5   0 34.988  69.976   0.321    4.15    4        9.7        1.8
   48   1   6   1 35.007  70.014   0.321    4.14    8        7.7        2.2
   49   3   0   1 35.498  70.995   0.325    4.03    4       15.2        4.3
   50   3   1   1 35.954  71.908   0.328    3.93    8       54.6      107.6
   51   3   2   0 35.981  71.961   0.328    3.92    4       35.0       22.0
   52   2   1   3 36.121  72.242   0.33     3.89    8       18.6       12.3
   53   2   4   2 36.253  72.506   0.331    3.87    8       41.2       60.2
   54   2   5   1 36.332  72.664   0.331    3.85    8       28.6       29.0
   55   0   0   4 36.601  73.202   0.333    3.8     2      201.3      352.7
   56   1   4   3 36.619  73.238   0.333    3.79    8       10.8        4.0
   57   0   6   2 36.915  73.831   0.336    3.74    4      168.6      487.0
   58   3   2   1 37.31   74.62    0.339    3.66    8       21.1       15.0
   59   2   2   3 37.474  74.949   0.34     3.63    8        9.4        2.9
   60   3   3   0 38.23   76.459   0.346    3.51    4       75.7       92.2
   61   0   2   4 38.393  76.786   0.347    3.48    4       29.3       13.7
   62   1   6   2 38.983  77.967   0.352    3.39    8       10.7        3.6
   63   1   1   4 39.117  78.234   0.353    3.37    8       25.0       19.3
   64   1   7   0 39.527  79.055   0.356    3.32    4      125.0      237.8
   65   3   3   1 39.532  79.065   0.356    3.32    8       63.5      122.7
   66   2   3   3 39.694  79.388   0.357    3.29    8       10.7        3.5
   67   3   1   2 39.896  79.792   0.359    3.27    8       80.7      195.4
   68   2   6   0 39.924  79.848   0.359    3.26    4        7.1        0.8
   69   2   5   2 40.261  80.522   0.361    3.22    8       15.5        7.1
   70   1   2   4 40.437  80.875   0.363    3.2     8        6.2        1.1
   71   1   5   3 40.616  81.231   0.364    3.18    8       31.3       28.5
   72   1   7   1 40.819  81.638   0.365    3.16    8        2.3        0.2
   73   3   2   2 41.21   82.42    0.368    3.12    8       63.2      114.2
   74   2   6   1 41.213  82.425   0.368    3.12    8       40.7       47.3
   75   3   4   0 41.311  82.623   0.369    3.11    4       49.4       34.7
   76   3   4   1 42.592  85.183   0.378    2.99    8       38.0       39.5
   77   1   3   4 42.618  85.235   0.378    2.98    8       93.5      239.6
   78   2   4   3 42.751  85.502   0.379    2.97    8       35.9       35.2
   79   3   3   2 43.384  86.767   0.384    2.93    8       11.0        3.3
   80   0   6   3 43.387  86.773   0.384    2.93    4       70.4       66.5
   81   0   4   4 43.644  87.288   0.386    2.91    4       67.6       60.9
   82   0   8   0 44.046  88.093   0.389    2.88    2       48.0       15.2
   83   1   7   2 44.653  89.306   0.393    2.85    8        9.8        2.5
   84   2   0   4 44.741  89.482   0.393    2.84    4       93.1      113.1


  X-ray diffraction powder data (I)...X-Ray wave length =  1.78892 (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   2   0  10.009  20.019  5.1462       222.2     13.3     13.6     5.6
    2   1   1   0  11.904  23.808  4.33632      202.4     12.1     12.3     5.6
    3   0   2   1  13.237  26.473  3.9064       187.7     11.3     11.4     5.6
    4   1   0   1  13.839  27.678  3.73946       91.1      5.5      5.5     5.6
    5   1   1   1  14.744  29.487  3.51468      860.2     51.6     52.3     5.6
    6   1   2   0  14.795  29.589  3.50283       79.1      4.7      4.8     5.6
    7   1   2   1  17.198  34.396  3.02514       39.3      2.4      2.4     5.7
    8   0   0   2  17.345  34.689  3.00035       76.0      4.6      4.6     5.7
    9   1   3   0  18.716  37.433  2.78747     1493.3     89.6     90.1     5.7
   10   0   2   2  20.187  40.374  2.59199      539.3     32.4     32.4     5.7
   11   0   4   0  20.342  40.684  2.5731       210.4     12.6     12.6     5.7
   12   1   3   1  20.721  41.442  2.52803     1151.8     69.1     69.2     5.7
   13   1   1   2  21.255  42.51   2.46732     1666.1    100.0    100.0     5.7
   14   2   0   0  21.971  43.943  2.3907       258.9     15.5     15.5     5.7
   15   0   4   1  22.224  44.448  2.36486      189.8     11.4     11.4     5.7
   16   2   1   0  22.588  45.176  2.3287        93.3      5.6      5.6     5.7
   17   1   2   2  23.112  46.224  2.2787       211.2     12.7     12.6     5.7
   18   1   4   0  23.251  46.502  2.26584      188.8     11.3     11.3     5.7
   19   2   1   1  24.331  48.662  2.17096       83.1      5.0      5.0     5.7
   20   1   3   2  25.976  51.952  2.04216      153.9      9.2      9.1     5.8
   21   0   4   2  27.255  54.509  1.9532        34.3      2.1      2.0     5.8
   22   1   5   0  28.235  56.469  1.89071       73.3      4.4      4.3     5.8
   23   1   1   3  29.502  59.005  1.81631      161.5      9.7      9.5     5.8
   24   1   5   1  29.736  59.473  1.80331      105.9      6.4      6.2     5.8
   25   2   2   2  30.596  61.193  1.75734     1235.5     74.2     72.4     5.8
   26   2   4   0  30.711  61.422  1.75142      397.5     23.9     23.3     5.8
   27   1   2   3  30.994  61.988  1.73698       31.7      1.9      1.9     5.8
   28   2   4   1  32.142  64.283  1.68127      169.4     10.2      9.9     5.9
   29   0   6   1  32.841  65.683  1.64933      159.1      9.5      9.3     5.9
   30   1   3   3  33.394  66.788  1.62512      272.5     16.4     15.8     5.9
   31   1   5   2  33.999  67.998  1.59959      262.1     15.7     15.2     5.9
   32   0   4   3  34.499  68.999  1.57921      110.7      6.6      6.4     5.9
   33   3   1   0  34.604  69.208  1.57503       86.0      5.2      5.0     5.9
   34   3   1   1  35.954  71.908  1.52343      129.6      7.8      7.5     5.9
   35   2   4   2  36.253  72.506  1.51257       60.2      3.6      3.5     5.9
   36   2   5   1  36.332  72.664  1.50973       29.0      1.7      1.7     6.0
   37   0   0   4  36.601  73.202  1.50017      356.7     21.4     20.5     6.0
   38   0   6   2  36.915  73.831  1.48919      487.0     29.2     27.9     6.0
   39   3   3   0  38.23   76.459  1.44544       92.2      5.5      5.3     6.0
   40   1   1   4  39.117  78.234  1.41773       19.3      1.2      1.1     6.0
   41   1   7   0  39.527  79.055  1.40539      360.6     21.6     20.5     6.0
   42   3   1   2  39.896  79.792  1.39456      196.2     11.8     11.1     6.0
   43   1   5   3  40.616  81.231  1.37402       28.5      1.7      1.6     6.1
   44   3   2   2  41.21   82.42   1.35767      161.6      9.7      9.1     6.1
   45   3   4   0  41.311  82.623  1.35493       34.7      2.1      2.0     6.1
   46   1   3   4  42.618  85.235  1.32101      279.1     16.8     15.6     6.1
   47   2   4   3  42.751  85.502  1.31768       35.2      2.1      2.0     6.1
   48   0   6   3  43.387  86.773  1.30213       69.8      4.2      3.9     6.1
   49   0   4   4  43.644  87.288  1.29599       60.9      3.7      3.4     6.2
   50   2   0   4  44.741  89.482  1.27071      113.1      6.8      6.3     6.2

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)