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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ARMALCOLITE

7, at 4.3 GPa

MgTi(2)O(5)


Orthorhombic  B bmm  Z = 4

Bbmm

15 .10 .1901

Ref.Str.:

         Yang H, Hazen R.M. (1999)

         * Amer. Mineral., 84, 130-137

Reserv:

         In original - karrooite[3].

         All structure data from 0.0 GPa upto 7.5 GPa

         see in the original.   N.A.D.

                   Initial data from BDM-file 

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

             a =   9.6349   alpha =   90.0 
             b =   9.9143   beta  =   90.0 
             c =   3.7168   gamma =   90.0 

    Unit cell volume (cub. angs.) =   355.04

    Molar volume ( cub.cm/mol.) =    53.46

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

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

   1 0.8044  0.25    0.0      0.44   Mg    = 0.93, Ti    = 0.07
   2 0.1336  0.4334  0.0      0.35   Ti    = 0.96, Mg    = 0.04
   3 0.2202  0.25    0.0      0.47   O     = 1.00
   4 0.0465  0.8856  0.0      0.58   O     = 1.00
   5 0.3142  0.9379  0.0      0.54   O     = 1.00


  Co-ordinates for all atomic positions :

   No       NoP      x/a        y/b       z/c 

     1       1     0.8044     0.25       0.0   
     2       2     0.1336     0.4334     0.0   
     3       3     0.2202     0.25       0.0   
     4       4     0.0465     0.8856     0.0   
     5       5     0.3142     0.9379     0.0   
     6       1     0.1956     0.75       0.0   
     7       2     0.8664     0.5666     0.0   
     8       3     0.7798     0.75       0.0   
     9       4     0.9535     0.1144     0.0   
    10       5     0.6858     0.0621     0.0   
    11       2     0.1336     0.0666     0.0   
    12       4     0.0465     0.6144     0.0   
    13       5     0.3142     0.5621     0.0   
    14       2     0.8664     0.9334     0.0   
    15       4     0.9535     0.3856     0.0   
    16       5     0.6858     0.4379     0.0   
    17       1     0.6956     0.75       0.5   
    18       2     0.3664     0.9334     0.5   
    19       3     0.2798     0.75       0.5   
    20       4     0.4535     0.3856     0.5   
    21       5     0.1858     0.4379     0.5   
    22       1     0.3044     0.25       0.5   
    23       2     0.6336     0.0666     0.5   
    24       3     0.7202     0.25       0.5   
    25       4     0.5465     0.6144     0.5   
    26       5     0.8142     0.5621     0.5   
    27       2     0.3664     0.5666     0.5   
    28       4     0.4535     0.1144     0.5   
    29       5     0.1858     0.0621     0.5   
    30       2     0.6336     0.4334     0.5   
    31       4     0.5465     0.8856     0.5   
    32       5     0.8142     0.9379     0.5   


X-ray density (g/cm cub.)   =      3.74

MU (1/cm) =     407.415    Mass attenuation coefficient (cm**2/g) =    108.868

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

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

    1   Mg   ,Ti             2.568        6
                                                 1.9675       4
                                                 2.1854       5
                                                 1.9675       4
                                                 2.1854       5
                                                 2.0278       3
                                                 2.0278       3
    2   Ti   ,Mg             2.568        6
                                                 2.0006       3
                                                 1.981        4
                                                 2.1578       5
                                                 1.7988       4
                                                 1.9258       5
                                                 1.9258       5
    3    O                   3.264       12
                                                 3.2241       5
                                                 2.9001       4
                                                 3.2241       5
                                                 2.9001       4
                                                 3.2115       4
                                                 3.2115       4
                                                 2.6521       5
                                                 2.6521       5
                                                 3.2115       4
                                                 3.2115       4
                                                 2.6521       5
                                                 2.6521       5
    4    O                   3.264       10
                                                 2.6309       5
                                                 2.9001       3
                                                 2.439        4
                                                 2.6888       4
                                                 3.2115       3
                                                 3.2115       3
                                                 2.8839       5
                                                 2.8839       5
                                                 2.955        5
                                                 2.955        5
    5    O                   3.264       10
                                                 3.2241       3
                                                 2.6309       4
                                                 2.6521       3
                                                 2.6521       3
                                                 2.8839       4
                                                 2.8839       4
                                                 2.5496       5
                                                 2.5496       5
                                                 2.955        4
                                                 2.955        4

  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   0   2   0  8.939  17.879   0.101   79.9     2       78.0      772.2
    2   2   0   0  9.201  18.401   0.104   75.3     2       69.7      580.6
    3   2   1   0 10.24   20.48    0.115   60.37    4       38.2      280.0
    4   1   0   1 12.834  25.668   0.144   37.67    4      142.5     2426.6
    5   2   2   0 12.883  25.766   0.145   37.37    4       26.0       80.3
    6   1   1   1 13.611  27.221   0.153   33.27    8        1.6        0.5
    7   1   2   1 15.729  31.458   0.176   24.42    8       34.7      186.2
    8   2   3   0 16.419  32.837   0.183   22.26    4      148.7     1561.1
    9   0   4   0 18.106  36.212   0.202   17.98    2        4.0        0.5
   10   3   0   1 18.48   36.96    0.206   17.19    4       75.9      314.1
   11   4   0   0 18.65   37.3     0.208   16.85    2       83.3      185.5
   12   1   3   1 18.782  37.565   0.209   16.59    8       54.1      308.2
   13   3   1   1 19.048  38.096   0.212   16.08    8       14.1       20.3
   14   4   1   0 19.214  38.427   0.214   15.78    4       31.7       50.2
   15   2   4   0 20.456  40.913   0.227   13.73    4       78.0      265.0
   16   3   2   1 20.672  41.343   0.229   13.41    8        6.3        3.4
   17   4   2   0 20.827  41.653   0.231   13.19    4       98.7      407.9
   18   1   4   1 22.457  44.915   0.248   11.13    8       27.9       55.2
   19   3   3   1 23.169  46.338   0.255   10.38    8       49.3      160.2
   20   4   3   0 23.311  46.621   0.257   10.23    4      105.1      358.4
   21   0   0   2 24.487  48.974   0.269    9.15    2      230.4      770.9
   22   2   5   0 24.84   49.68    0.273    8.86    4      111.3      348.2
   23   0   2   2 26.273  52.547   0.287    7.8     4       50.2       62.4
   24   3   4   1 26.354  52.707   0.288    7.74    8       47.0      108.4
   25   2   0   2 26.376  52.752   0.288    7.73    4       46.7       53.4
   26   4   4   0 26.482  52.965   0.289    7.66    4       16.7        6.7
   27   1   5   1 26.583  53.166   0.29     7.59    8       30.3       44.3
   28   5   0   1 26.761  53.521   0.292    7.48    4       32.9       25.7
   29   2   1   2 26.808  53.616   0.293    7.45    8       25.5       30.7
   30   5   1   1 27.188  54.377   0.297    7.21    8       38.4       67.3
   31   0   6   0 27.786  55.571   0.303    6.86    2      162.9      288.8
   32   2   2   2 28.076  56.153   0.306    6.7     8       19.1       15.5
   33   5   2   1 28.445  56.891   0.309    6.51    8       94.8      371.4
   34   6   0   0 28.665  57.329   0.311    6.4     2       56.6       32.5
   35   6   1   0 29.074  58.147   0.315    6.2     4       63.1       78.2
   36   2   6   0 29.526  59.053   0.32     5.98    4       50.1       47.6
   37   3   5   1 30.091  60.183   0.325    5.73    8       71.3      184.8
   38   2   3   2 30.112  60.224   0.326    5.73    8      111.1      448.2
   39   4   5   0 30.209  60.419   0.327    5.68    4       14.4        3.7
   40   6   2   0 30.28   60.559   0.327    5.66    4       28.0       14.1
   41   5   3   1 30.465  60.93    0.329    5.58    8      104.5      386.7
   42   1   6   1 31.09   62.18    0.335    5.33    8       66.3      148.9
   43   0   4   2 31.202  62.404   0.336    5.29    4        6.5        0.7
   44   4   0   2 31.568  63.136   0.34     5.16    4       66.6       72.7
   45   4   1   2 31.954  63.909   0.344    5.02    8       16.4        8.6
   46   6   3   0 32.229  64.459   0.346    4.93    4       76.6       91.8
   47   2   4   2 32.831  65.663   0.352    4.74    8       54.2       88.2
   48   4   2   2 33.099  66.198   0.354    4.65    8       74.4      163.6
   49   5   4   1 33.168  66.337   0.355    4.63    8       39.6       46.0
   50   3   6   1 34.313  68.627   0.366    4.32    8       65.7      118.1
   51   4   6   0 34.424  68.847   0.367    4.29    4       52.4       37.4
   52   2   7   0 34.533  69.065   0.368    4.26    4       51.1       35.3
   53   6   4   0 34.859  69.717   0.371    4.18    4        8.5        1.0
   54   4   3   2 34.963  69.927   0.372    4.15    8       76.9      156.1
   55   1   7   1 35.978  71.955   0.381    3.92    8       24.0       14.3
   56   2   5   2 36.167  72.335   0.383    3.88    8       83.6      172.4
   57   5   5   1 36.49   72.98    0.386    3.82    8       34.3       28.5
   58   7   0   1 36.639  73.278   0.387    3.79    4       45.9       25.4
   59   7   1   1 36.999  73.999   0.391    3.72    8       57.1       77.1
   60   4   4   2 37.503  75.006   0.395    3.63    8       13.4        4.1
   61   7   2   1 38.073  76.146   0.4      3.53    8       82.5      152.7
   62   6   5   0 38.116  76.232   0.401    3.52    4       56.7       35.9
   63   0   8   0 38.429  76.859   0.403    3.48    2       47.7       12.6
   64   0   6   2 38.593  77.186   0.405    3.45    4      126.1      174.0
   65   1   0   3 38.818  77.636   0.407    3.42    4       77.2       64.5
   66   3   7   1 39.012  78.025   0.409    3.39    8       25.6       14.0
   67   4   7   0 39.117  78.234   0.41     3.37    4        9.9        1.0
   68   1   1   3 39.172  78.343   0.41     3.37    8        0.7        0.0
   69   6   0   2 39.342  78.684   0.412    3.34    4       44.6       21.1
   70   6   1   2 39.694  79.389   0.415    3.29    8       51.0       54.4
   71   8   0   0 39.76   79.52    0.415    3.29    2       15.5        1.3
   72   7   3   1 39.842  79.684   0.416    3.27    8       44.1       40.5
   73   2   8   0 39.925  79.85    0.417    3.26    4        9.7        1.0
   74   2   6   2 40.087  80.174   0.418    3.24    8       38.9       31.2
   75   8   1   0 40.111  80.223   0.418    3.24    4        3.1        0.1
   76   1   2   3 40.227  80.454   0.419    3.23    8       22.4       10.3
   77   5   6   1 40.399  80.798   0.421    3.21    8       11.7        2.8
   78   4   5   2 40.685  81.37    0.423    3.17    8        9.7        1.9
   79   6   2   2 40.747  81.493   0.424    3.17    8       21.1        8.9
   80   8   2   0 41.161  82.322   0.427    3.12    4       52.0       26.8
   81   1   8   1 41.304  82.607   0.428    3.11    8       16.5        5.3
   82   3   0   3 41.789  83.577   0.433    3.06    4       56.4       30.9
   83   1   3   3 41.973  83.946   0.434    3.04    8       44.5       38.2
   84   6   6   0 41.981  83.962   0.434    3.04    4       35.3       12.0
   85   3   1   3 42.137  84.273   0.435    3.03    8       14.2        3.9
   86   7   4   1 42.287  84.573   0.437    3.01    8       23.9       10.9
   87   6   3   2 42.488  84.977   0.438    3.0     8       61.9       72.9
   88   8   3   0 42.9    85.8     0.442    2.96    4       21.1        4.2
   89   3   2   3 43.178  86.355   0.444    2.94    8        2.0        0.1
   90   3   8   1 44.244  88.487   0.453    2.87    8       27.7       14.0
   91   4   8   0 44.346  88.692   0.454    2.86    4       89.7       73.2
   92   1   4   3 44.399  88.799   0.454    2.86    8       13.4        3.3
   93   4   6   2 44.506  89.011   0.455    2.85    8       44.7       36.2
   94   2   7   2 44.607  89.214   0.456    2.85    8       41.1       30.6
   95   3   3   3 44.908  89.816   0.458    2.83    8       31.8       18.2
   96   6   4   2 44.913  89.825   0.458    2.83    8        6.9        0.9
   97   5   7   1 44.915  89.83    0.458    2.83    8        1.4        0.0


  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   2   0   8.939  17.879  4.95715      772.2     31.8     32.0     5.6
    2   2   0   0   9.201  18.401  4.81745      580.6     23.9     24.0     5.6
    3   2   1   0  10.24   20.48   4.333        280.0     11.5     11.6     5.6
    4   1   0   1  12.834  25.668  3.46772     2426.6    100.0    100.0     5.6
    5   2   2   0  12.883  25.766  3.45478       80.3      3.3      3.3     5.6
    6   1   2   1  15.729  31.458  2.84148      186.2      7.7      7.6     5.6
    7   2   3   0  16.419  32.837  2.72517     1561.1     64.3     64.0     5.6
    8   3   0   1  18.48   36.96   2.4301       314.1     12.9     12.8     5.7
    9   4   0   0  18.65   37.3    2.40873      185.5      7.6      7.6     5.7
   10   1   3   1  18.782  37.565  2.39236      308.2     12.7     12.6     5.7
   11   4   1   0  19.214  38.427  2.34064       50.2      2.1      2.0     5.7
   12   2   4   0  20.456  40.913  2.20397      265.0     10.9     10.8     5.7
   13   4   2   0  20.827  41.653  2.1665       407.9     16.8     16.6     5.7
   14   1   4   1  22.457  44.915  2.01645       55.2      2.3      2.2     5.7
   15   3   3   1  23.169  46.338  1.95778      160.2      6.6      6.5     5.7
   16   4   3   0  23.311  46.621  1.94655      358.4     14.8     14.5     5.7
   17   0   0   2  24.487  48.974  1.8584       770.9     31.8     31.1     5.7
   18   2   5   0  24.84   49.68   1.83361      348.2     14.3     14.0     5.7
   19   0   2   2  26.273  52.547  1.74014       62.4      2.6      2.5     5.8
   20   3   4   1  26.354  52.707  1.73522      161.8      6.7      6.5     5.8
   21   1   5   1  26.583  53.166  1.72133       44.3      1.8      1.8     5.8
   22   5   0   1  26.761  53.521  1.71073       25.7      1.1      1.0     5.8
   23   2   1   2  26.808  53.616  1.70794       30.7      1.3      1.2     5.8
   24   5   1   1  27.188  54.377  1.68582       67.3      2.8      2.7     5.8
   25   0   6   0  27.786  55.571  1.65238      288.8     11.9     11.5     5.8
   26   5   2   1  28.445  56.891  1.61714      371.4     15.3     14.8     5.8
   27   6   0   0  28.665  57.329  1.60582       32.5      1.3      1.3     5.8
   28   6   1   0  29.074  58.147  1.58516       78.2      3.2      3.1     5.8
   29   2   6   0  29.526  59.053  1.563         47.6      2.0      1.9     5.8
   30   2   3   2  30.112  60.224  1.53538      633.0     26.1     25.1     5.8
   31   5   3   1  30.465  60.93   1.51925      386.7     15.9     15.3     5.8
   32   1   6   1  31.09   62.18   1.49169      148.9      6.1      5.9     5.8
   33   4   0   2  31.568  63.136  1.47138       72.7      3.0      2.9     5.9
   34   6   3   0  32.229  64.459  1.44433       91.8      3.8      3.6     5.9
   35   2   4   2  32.831  65.663  1.42074       88.2      3.6      3.5     5.9
   36   4   2   2  33.099  66.198  1.41055      163.6      6.7      6.4     5.9
   37   5   4   1  33.168  66.337  1.40793       46.0      1.9      1.8     5.9
   38   3   6   1  34.313  68.627  1.36642      118.1      4.9      4.6     5.9
   39   4   6   0  34.424  68.847  1.36259       37.4      1.5      1.5     5.9
   40   2   7   0  34.533  69.065  1.35882       35.3      1.5      1.4     5.9
   41   4   3   2  34.963  69.927  1.34417      156.1      6.4      6.1     5.9
   42   2   5   2  36.167  72.335  1.30524      172.4      7.1      6.7     5.9
   43   5   5   1  36.49   72.98   1.29528       28.5      1.2      1.1     6.0
   44   7   0   1  36.639  73.278  1.29075       25.4      1.0      1.0     6.0
   45   7   1   1  36.999  73.999  1.27995       77.1      3.2      3.0     6.0
   46   7   2   1  38.073  76.146  1.2491       152.7      6.3      5.9     6.0
   47   6   5   0  38.116  76.232  1.24791       35.9      1.5      1.4     6.0
   48   0   6   2  38.593  77.186  1.23485      174.0      7.2      6.7     6.0
   49   1   0   3  38.818  77.636  1.22882       64.5      2.7      2.5     6.0
   50   6   1   2  39.694  79.389  1.20603       54.4      2.2      2.1     6.0
   51   7   3   1  39.842  79.684  1.2023        40.5      1.7      1.6     6.0
   52   2   6   2  40.087  80.174  1.19618       31.3      1.3      1.2     6.0
   53   8   2   0  41.161  82.322  1.17032       26.8      1.1      1.0     6.1
   54   3   0   3  41.789  83.577  1.15591       30.9      1.3      1.2     6.1
   55   1   3   3  41.973  83.946  1.15177       50.2      2.1      1.9     6.1
   56   6   3   2  42.488  84.977  1.14041       72.9      3.0      2.8     6.1
   57   4   8   0  44.346  88.692  1.10199       73.2      3.0      2.7     6.2
   58   4   6   2  44.506  89.011  1.09886       36.2      1.5      1.4     6.2
   59   2   7   2  44.607  89.214  1.09689       30.6      1.3      1.1     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)