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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TEPHROITE

4, t-olivine, syn, f-olivine, s-forsterite

MnMgSiO(4)


Orthorhombic  P nma  Z = 4

Pnma

17 .4 .17

Ref.Str.:

         Yamazaki S., Toraya H. (1999)

         * J. Applied Cryst., 32,51-59

         R: N.A.D.

                   Initial data from BDM-file 

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

             a =  10.451    alpha =   90.0 
             b =   6.1245   beta  =   90.0 
             c =   4.8076   gamma =   90.0 

    Unit cell volume (cub. angs.) =   307.72

    Molar volume ( cub.cm/mol.) =    46.34

  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    Mn    = 0.29, Mg    = 0.7 
   2 0.2791  0.25    0.9879   0.0    Mn    = 0.7 , Mg    = 0.29
   3 0.0928  0.25    0.4243   0.0    Si    = 1.00
   4 0.089   0.25    0.7572   0.0    O     = 1.00
   5 0.4516  0.25    0.2261   0.0    O     = 1.00
   6 0.1607  0.0392  0.2782   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     0.2791     0.25       0.9879
     3       3     0.0928     0.25       0.4243
     4       4     0.089      0.25       0.7572
     5       5     0.4516     0.25       0.2261
     6       6     0.1607     0.0392     0.2782
     7       1     0.5        0.0        0.5   
     8       2     0.2209     0.75       0.4879
     9       3     0.4072     0.75       0.9243
    10       4     0.411      0.75       0.2572
    11       5     0.0484     0.75       0.7261
    12       6     0.3393     0.9608     0.7782
    13       1     0.5        0.5        0.5   
    14       6     0.3393     0.5392     0.7782
    15       1     0.0        0.5        0.0   
    16       6     0.1607     0.4608     0.2782
    17       2     0.7791     0.25       0.5121
    18       3     0.5928     0.25       0.0757
    19       4     0.589      0.25       0.7428
    20       5     0.9516     0.25       0.2739
    21       6     0.6607     0.0392     0.2218
    22       2     0.7209     0.75       0.0121
    23       3     0.9072     0.75       0.5757
    24       4     0.911      0.75       0.2428
    25       5     0.5484     0.75       0.7739
    26       6     0.8393     0.9608     0.7218
    27       6     0.8393     0.5392     0.7218
    28       6     0.6607     0.4608     0.2218


X-ray density (g/cm cub.)   =      3.7 

MU (1/cm) =     112.33     Mass attenuation coefficient (cm**2/g) =     30.385

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

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

    1   Mn   ,Mg             2.724        6
                                                 2.1382       4
                                                 2.1603       6
                                                 2.0819       5
                                                 2.0819       5
                                                 2.1382       4
                                                 2.1603       6
    2   Mn   ,Mg             2.724        6
                                                 2.2754       4
                                                 2.1358       5
                                                 2.2684       6
                                                 2.1329       6
                                                 2.1329       6
                                                 2.2684       6
    3    Si                  2.1          4
                                                 1.6009       4
                                                 1.6321       6
                                                 1.6321       6
                                                 1.6433       5
    4    O                   3.264       12
                                                 2.9158       6
                                                 2.7443       6
                                                 3.0951       5
                                                 3.0951       5
                                                 3.1607       6
                                                 3.1607       6
                                                 2.9158       6
                                                 2.7443       6
                                                 2.8693       5
                                                 2.7314       5
                                                 3.1585       6
                                                 3.1585       6
    5    O                   3.264        8
                                                 3.0951       4
                                                 3.0951       4
                                                 3.0251       6
                                                 3.0251       6
                                                 2.8693       4
                                                 2.7314       4
                                                 2.5383       6
                                                 2.5383       6
    6    O                   3.264        9
                                                 2.7443       4
                                                 2.9158       4
                                                 3.1607       4
                                                 3.0251       5
                                                 3.081        6
                                                 3.081        6
                                                 2.5821       6
                                                 2.5383       5
                                                 3.1585       4

  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   2   0   0  9.856  19.712   0.096   65.34    2       15.8       34.3
    2   1   0   1 11.817  23.635   0.114   44.8     4        1.7        0.6
    3   2   1   0 13.003  26.007   0.126   36.64    4       37.0      211.7
    4   0   1   1 13.682  27.363   0.132   32.91    4       27.8      107.5
    5   1   1   1 14.568  29.137   0.141   28.79    8       47.9      556.9
    6   2   0   1 14.644  29.288   0.141   28.47    4       28.6       98.6
    7   2   1   1 16.976  33.952   0.163   20.7     8       16.5       47.8
    8   0   2   0 16.983  33.967   0.163   20.68    2       65.8      189.1
    9   3   0   1 18.486  36.973   0.177   17.18    4       95.9      668.2
   10   2   2   0 19.789  39.578   0.189   14.78    4       46.2      133.3
   11   4   0   0 20.02   40.04    0.191   14.4     2       33.8       34.8
   12   3   1   1 20.432  40.864   0.195   13.76    8       85.5      850.5
   13   1   2   1 20.9    41.8     0.199   13.09    8       86.1      819.2
   14   0   0   2 21.845  43.691   0.208   11.85    2       46.9       55.0
   15   4   1   0 21.851  43.702   0.208   11.84    4       58.0      168.2
   16   1   0   2 22.446  44.893   0.213   11.15    4       38.0       68.1
   17   2   2   1 22.725  45.45    0.216   10.84    8       47.3      205.2
   18   4   0   1 22.932  45.864   0.218   10.62    4       60.0      161.4
   19   1   1   2 24.129  48.259   0.229    9.46    8       32.5       84.6
   20   2   0   2 24.179  48.358   0.229    9.42    4       11.2        5.0
   21   4   1   1 24.589  49.178   0.233    9.07    8        1.5        0.2
   22   3   2   1 25.538  51.077   0.241    8.32    8       15.4       16.6
   23   2   1   2 25.776  51.551   0.243    8.14    8       16.8       19.4
   24   4   2   0 26.745  53.49    0.252    7.49    4        8.3        2.2
   25   3   0   2 26.878  53.756   0.253    7.4     4       19.5       11.9
   26   5   0   1 27.816  55.631   0.261    6.85    4       24.3       17.1
   27   2   3   0 28.06   56.119   0.263    6.71    4        4.8        0.7
   28   0   2   2 28.233  56.466   0.264    6.62    4       28.8       23.1
   29   3   1   2 28.366  56.731   0.266    6.55    8        0.4        0.0
   30   0   3   1 28.425  56.85    0.266    6.52    4       12.9        4.6
   31   1   2   2 28.733  57.467   0.269    6.36    8       13.8       10.2
   32   1   3   1 28.923  57.847   0.27     6.27    8       43.3       99.5
   33   4   2   1 29.141  58.282   0.272    6.16    8        2.1        0.2
   34   5   1   1 29.271  58.543   0.273    6.1     8       31.7       51.8
   35   2   2   2 30.203  60.407   0.281    5.69    8      118.0      668.8
   36   4   0   2 30.373  60.746   0.283    5.62    4       93.1      205.7
   37   2   3   1 30.388  60.775   0.283    5.61    8       26.4       33.1
   38   6   0   0 30.898  61.797   0.287    5.41    2        3.5        0.1
   39   4   1   2 31.756  63.512   0.294    5.09    8       57.4      141.7
   40   6   1   0 32.268  64.536   0.298    4.92    4       80.3      134.1
   41   3   2   2 32.564  65.128   0.301    4.82    8       16.0       10.4
   42   3   3   1 32.741  65.482   0.302    4.76    8       70.8      202.0
   43   6   0   1 33.105  66.211   0.305    4.65    4       20.7        8.4
   44   5   2   1 33.402  66.804   0.308    4.57    8       51.6      102.7
   45   4   3   0 33.782  67.563   0.311    4.46    4       72.6       99.4
   46   1   0   3 34.38   68.76    0.316    4.3     4       38.6       27.0
   47   6   1   1 34.428  68.856   0.316    4.29    8        6.6        1.6
   48   5   0   2 34.547  69.095   0.317    4.26    4        3.6        0.2
   49   0   1   3 35.236  70.472   0.323    4.09    4       15.0        3.9
   50   1   3   2 35.533  71.065   0.325    4.02    8       21.9       16.3
   51   1   1   3 35.68   71.361   0.326    3.99    8       46.2       72.1
   52   2   0   3 35.719  71.439   0.326    3.98    4       30.8       15.9
   53   4   2   2 35.728  71.456   0.326    3.98    8       24.4       20.0
   54   0   4   0 35.746  71.491   0.327    3.97    2      166.9      233.9
   55   5   1   2 35.845  71.689   0.327    3.95    8       31.5       33.1
   56   4   3   1 35.897  71.794   0.328    3.94    8       13.9        6.4
   57   6   2   0 36.212  72.424   0.33     3.87    4      133.9      293.4
   58   2   3   2 36.854  73.708   0.335    3.75    8       10.6        3.6
   59   2   1   3 36.999  73.999   0.336    3.72    8       20.9       13.8
   60   2   4   0 37.499  74.998   0.34     3.63    4       14.1        3.1
   61   3   0   3 37.907  75.814   0.343    3.56    4       52.0       40.7
   62   1   4   1 38.246  76.493   0.346    3.5     8        1.7        0.1
   63   6   2   1 38.271  76.542   0.346    3.5     8        6.7        1.3
   64   7   0   1 38.853  77.706   0.351    3.41    4       95.7      131.9
   65   3   3   2 39.018  78.036   0.352    3.39    8        8.2        1.9
   66   3   1   3 39.161  78.322   0.353    3.37    8       50.6       73.0
   67   6   0   2 39.358  78.716   0.354    3.34    4       11.0        1.7
   68   1   2   3 39.476  78.952   0.355    3.32    8       50.3       71.2
   69   2   4   1 39.535  79.07    0.356    3.32    8        7.5        1.6
   70   5   2   2 39.635  79.27    0.357    3.3     8       14.3        5.7
   71   5   3   1 39.798  79.596   0.358    3.28    8       22.2       13.7
   72   7   1   1 40.098  80.197   0.36     3.24    8        8.7        2.1
   73   6   1   2 40.599  81.198   0.364    3.18    8       31.1       26.0
   74   2   2   3 40.754  81.507   0.365    3.17    8       68.3      124.6
   75   4   0   3 40.903  81.806   0.366    3.15    4       54.0       38.7
   76   3   4   1 41.659  83.318   0.372    3.07    8       64.9      109.2
   77   4   3   2 41.994  83.988   0.374    3.04    8       31.8       25.9
   78   4   1   3 42.134  84.269   0.375    3.03    8       36.7       34.4
   79   6   3   0 42.457  84.913   0.377    3.0     4       62.6       49.6
   80   4   4   0 42.618  85.236   0.379    2.98    4       35.6       16.0
   81   3   2   3 42.866  85.731   0.38     2.96    8        4.8        0.6
   82   8   0   0 43.211  86.422   0.383    2.94    2       19.3        2.3
   83   7   2   1 43.788  87.577   0.387    2.9     8       28.2       19.4
   84   0   4   2 43.839  87.678   0.387    2.89    4       58.0       41.2
   85   1   4   2 44.259  88.517   0.39     2.87    8       23.3       13.1
   86   6   2   2 44.283  88.565   0.39     2.87    8       34.6       29.1
   87   8   1   0 44.434  88.869   0.391    2.86    4        1.3        0.0
   88   6   3   1 44.443  88.886   0.391    2.86    8       17.9        7.7
   89   4   4   1 44.604  89.208   0.393    2.85    8       24.1       14.0
   90   5   0   3 44.694  89.389   0.393    2.84    4        8.8        0.9
   91   7   0   2 44.85   89.7     0.394    2.84    4       18.9        4.3


  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   2   0   0   9.856  19.712  5.2255        34.3      4.0      4.1     5.6
    2   2   1   0  13.003  26.007  3.97519      211.7     24.9     25.2     5.6
    3   0   1   1  13.682  27.363  3.78163      107.5     12.6     12.8     5.6
    4   1   1   1  14.568  29.137  3.55599      556.9     65.5     66.2     5.6
    5   2   0   1  14.644  29.288  3.538         98.6     11.6     11.7     5.6
    6   0   2   0  16.983  33.967  3.06223      236.9     27.9     28.0     5.7
    7   3   0   1  18.486  36.973  2.82092      668.2     78.6     78.9     5.7
    8   2   2   0  19.789  39.578  2.642        133.3     15.7     15.7     5.7
    9   4   0   0  20.02   40.04   2.61275       34.8      4.1      4.1     5.7
   10   3   1   1  20.432  40.864  2.5622       850.5    100.0    100.0     5.7
   11   1   2   1  20.9    41.8    2.50735      819.2     96.3     96.2     5.7
   12   4   1   0  21.851  43.702  2.4032       223.2     26.2     26.2     5.7
   13   1   0   2  22.446  44.893  2.34262       68.1      8.0      8.0     5.7
   14   2   2   1  22.725  45.45   2.3154       205.2     24.1     24.0     5.7
   15   4   0   1  22.932  45.864  2.29564      161.4     19.0     18.9     5.7
   16   1   1   2  24.129  48.259  2.18802       84.6      9.9      9.9     5.7
   17   3   2   1  25.538  51.077  2.07476       16.6      2.0      1.9     5.8
   18   2   1   2  25.776  51.551  2.05695       19.4      2.3      2.3     5.8
   19   3   0   2  26.878  53.756  1.97849       11.9      1.4      1.4     5.8
   20   5   0   1  27.816  55.631  1.91687       17.1      2.0      2.0     5.8
   21   0   2   2  28.233  56.466  1.89082       23.1      2.7      2.7     5.8
   22   1   2   2  28.733  57.467  1.86061       10.2      1.2      1.2     5.8
   23   1   3   1  28.923  57.847  1.84943       99.5     11.7     11.5     5.8
   24   5   1   1  29.271  58.543  1.82936       51.8      6.1      6.0     5.8
   25   2   2   2  30.203  60.407  1.778        668.8     78.6     76.8     5.8
   26   4   0   2  30.373  60.746  1.769        238.8     28.1     27.4     5.8
   27   4   1   2  31.756  63.512  1.69953      141.7     16.7     16.2     5.9
   28   6   1   0  32.268  64.536  1.67539      134.1     15.8     15.3     5.9
   29   3   2   2  32.564  65.128  1.66181       10.4      1.2      1.2     5.9
   30   3   3   1  32.741  65.482  1.65383      202.0     23.7     23.0     5.9
   31   5   2   1  33.402  66.804  1.62479      102.7     12.1     11.7     5.9
   32   4   3   0  33.782  67.563  1.60866       99.4     11.7     11.3     5.9
   33   1   0   3  34.38   68.76   1.58401       27.0      3.2      3.1     5.9
   34   1   3   2  35.533  71.065  1.53908       16.3      1.9      1.8     5.9
   35   1   1   3  35.68   71.361  1.53355       72.1      8.5      8.1     5.9
   36   0   4   0  35.746  71.491  1.53112      269.9     31.7     30.4     5.9
   37   5   1   2  35.845  71.689  1.52745       33.1      3.9      3.7     5.9
   38   6   2   0  36.212  72.424  1.51404      293.4     34.5     33.0     5.9
   39   2   1   3  36.999  73.999  1.4863        13.8      1.6      1.5     6.0
   40   3   0   3  37.907  75.814  1.45587       40.7      4.8      4.5     6.0
   41   7   0   1  38.853  77.706  1.42583      131.9     15.5     14.7     6.0
   42   3   1   3  39.161  78.322  1.4164        73.0      8.6      8.1     6.0
   43   1   2   3  39.476  78.952  1.40693       71.2      8.4      7.9     6.0
   44   5   3   1  39.798  79.596  1.39741       13.7      1.6      1.5     6.0
   45   6   1   2  40.599  81.198  1.37448       26.0      3.1      2.9     6.1
   46   2   2   3  40.754  81.507  1.37017      124.6     14.6     13.7     6.1
   47   4   0   3  40.903  81.806  1.36604       38.7      4.6      4.3     6.1
   48   3   4   1  41.659  83.318  1.34567      109.2     12.8     12.0     6.1
   49   4   3   2  41.994  83.988  1.33691       25.9      3.0      2.8     6.1
   50   4   1   3  42.134  84.269  1.33328       34.4      4.0      3.8     6.1
   51   6   3   0  42.457  84.913  1.32506       49.6      5.8      5.4     6.1
   52   4   4   0  42.618  85.236  1.321         16.0      1.9      1.8     6.1
   53   7   2   1  43.788  87.577  1.29258       19.4      2.3      2.1     6.2
   54   0   4   2  43.839  87.678  1.29139       41.2      4.8      4.5     6.2
   55   6   2   2  44.283  88.565  1.2811        42.2      5.0      4.6     6.2
   56   4   4   1  44.604  89.208  1.27379       14.0      1.6      1.5     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)