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

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DAWSONITE

1

NaAl(OH)(2)CO(3)


Orthorhombic  I mma  Z = 4

R =0.058          NR =406

24 .10 .1996

Ref.Str.:

         E. Corazza, C. Sabelli, S. Vannucci (1977)

         * Neues Jb. Miner., Mh., 381-397

Reserv:

         N.A.D.

                   Initial data from BDM-file 

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

             a =   6.759    alpha =   90.0 
             b =   5.585    beta  =   90.0 
             c =  10.425    gamma =   90.0 

    Unit cell volume (cub. angs.) =   393.53

    Molar volume ( cub.cm/mol.) =    59.26

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

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

   1 0.0     0.0     0.5      0.0    Al    = 1.00
   2 0.25    0.75    0.25     0.0    Na    = 1.00
   3 0.0     0.25    0.2526   0.0    C     = 1.00
   4 0.0     0.25    0.1326   0.0    O     = 1.00
   5 0.0     0.0474  0.3156   0.0    O     = 1.00
   6 0.1811  0.25    0.525    0.0    O     = 1.00
   7 0.275   0.25    0.478    0.0    H     = 1.00


  Co-ordinates for all atomic positions :

   No       NoP      x/a        y/b       z/c 

     1       1     0.0        0.0        0.5   
     2       2     0.25       0.75       0.25  
     3       3     0.0        0.25       0.2526
     4       4     0.0        0.25       0.1326
     5       5     0.0        0.0474     0.3156
     6       6     0.1811     0.25       0.525 
     7       7     0.275      0.25       0.478 
     8       1     0.5        0.0        0.0   
     9       2     0.25       0.25       0.75  
    10       3     0.5        0.75       0.7526
    11       4     0.5        0.75       0.6326
    12       5     0.5        0.9526     0.8156
    13       6     0.3189     0.75       0.025 
    14       7     0.225      0.75       0.978 
    15       2     0.75       0.75       0.25  
    16       6     0.8189     0.25       0.525 
    17       7     0.725      0.25       0.478 
    18       2     0.75       0.25       0.75  
    19       6     0.6811     0.75       0.025 
    20       7     0.775      0.75       0.978 
    21       3     0.5        0.25       0.2474
    22       4     0.5        0.25       0.3674
    23       5     0.5        0.0474     0.1844
    24       6     0.6811     0.25       0.975 
    25       7     0.775      0.25       0.022 
    26       3     0.0        0.75       0.7474
    27       4     0.0        0.75       0.8674
    28       5     0.0        0.9526     0.6844
    29       6     0.8189     0.75       0.475 
    30       7     0.725      0.75       0.522 
    31       6     0.3189     0.25       0.975 
    32       7     0.225      0.25       0.022 
    33       6     0.1811     0.75       0.475 
    34       7     0.275      0.75       0.522 
    35       1     0.0        0.5        0.5   
    36       5     0.0        0.4526     0.3156
    37       1     0.5        0.5        0.0   
    38       5     0.5        0.5474     0.8156
    39       5     0.5        0.4526     0.1844
    40       5     0.0        0.5474     0.6844


X-ray density (g/cm cub.)   =      2.43

MU (1/cm) =      50.27     Mass attenuation coefficient (cm**2/g) =     20.691

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

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

    1    Al                  2.316        6
                                                 1.9405       5
                                                 1.875        6
                                                 1.875        6
                                                 1.9405       5
                                                 1.875        6
                                                 1.875        6
    2    Na                  2.808        6
                                                 2.4661       5
                                                 2.3914       6
                                                 2.4661       5
                                                 2.3914       6
                                                 2.4661       5
                                                 2.4661       5
    3    C                   1.872        3
                                                 1.251        4
                                                 1.3083       5
                                                 1.3083       5
    4    O                   3.264        4
                                                 2.2181       5
                                                 2.7102       6
                                                 2.7102       6
                                                 2.2181       5
    5    O                   3.264        6
                                                 2.2181       4
                                                 2.7467       6
                                                 2.7467       6
                                                 2.6493       6
                                                 2.6493       6
                                                 2.263        5
    6    O                   3.264        8
                                                 2.7467       5
                                                 2.4481       6
                                                 2.7102       4
                                                 2.6493       5
                                                 2.8407       6
                                                 2.8407       6
                                                 2.7467       5
                                                 2.6493       5
    7    H                   1.632        1
                                                 0.8018       6

  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   1  7.806  15.612   0.088  105.47    4       74.8     1523.5
    2   0   0   2  8.498  16.996   0.096   88.65    2        5.5        3.4
    3   0   1   1  9.002  18.003   0.102   78.76    4        9.9       20.1
    4   2   0   0 13.175  26.35    0.148   35.64    2       61.2      172.2
    5   1   1   2 13.418  26.836   0.151   34.29    8       21.1       79.1
    6   1   0   3 14.433  28.866   0.162   29.37    4       29.9       67.9
    7   0   1   3 15.133  30.267   0.169   26.54    4        9.2        5.8
    8   2   0   2 15.762  31.524   0.176   24.31    4       11.3        8.1
    9   0   2   0 16.012  32.024   0.179   23.5     2       49.1       73.2
   10   2   1   1 16.049  32.098   0.179   23.38    8       85.5      883.4
   11   0   0   4 17.191  34.381   0.192   20.15    2      102.3      272.3
   12   1   2   1 17.906  35.813   0.2     18.43    8       49.5      233.5
   13   0   2   2 18.236  36.472   0.203   17.7     4       15.0       10.3
   14   1   1   4 20.211  40.423   0.224   14.1     8       19.9       28.9
   15   2   1   3 20.277  40.555   0.225   14.0     8       26.1       49.3
   16   3   0   1 20.474  40.948   0.227   13.7     4        0.9        0.0
   17   2   2   0 20.967  41.933   0.232   12.99    4       98.9      328.0
   18   1   2   3 21.825  43.649   0.241   11.87    8       25.8       41.0
   19   2   0   4 21.915  43.83    0.242   11.76    4       30.7       28.6
   20   1   0   5 22.744  45.488   0.251   10.82    4       91.0      231.4
   21   2   2   2 22.777  45.553   0.251   10.78    8       22.7       28.6
   22   0   1   5 23.225  46.45    0.256   10.32    4       65.5      114.2
   23   3   1   2 23.402  46.803   0.258   10.14    8        1.4        0.1
   24   0   2   4 23.846  47.691   0.262    9.72    4       24.6       15.2
   25   3   0   3 24.045  48.091   0.264    9.54    4       17.2        7.3
   26   0   3   1 24.854  49.708   0.273    8.85    4       36.4       30.3
   27   0   0   6 26.316  52.633   0.288    7.77    2       47.8       22.9
   28   3   2   1 26.453  52.906   0.289    7.68    8       86.9      299.8
   29   1   3   2 26.994  53.988   0.295    7.33    8       40.2       61.2
   30   2   1   5 27.096  54.191   0.296    7.27    8       33.3       41.5
   31   4   0   0 27.12   54.24    0.296    7.25    2      118.2      130.9
   32   2   2   4 27.652  55.304   0.301    6.94    8       83.8      251.8
   33   0   3   3 27.995  55.99    0.305    6.75    4       22.2        8.6
   34   3   1   4 28.197  56.394   0.307    6.64    8       11.9        4.9
   35   1   2   5 28.355  56.71    0.308    6.56    8       37.1       46.6
   36   1   1   6 28.559  57.118   0.31     6.45    8       11.0        4.0
   37   2   3   1 28.563  57.126   0.31     6.45    8       29.1       28.2
   38   4   0   2 28.634  57.267   0.311    6.41    4       31.5       16.4
   39   4   1   1 28.813  57.627   0.313    6.32    8        3.7        0.5
   40   3   2   3 29.475  58.951   0.319    6.01    8       20.9       13.5
   41   2   0   6 29.9    59.8     0.324    5.82    4       63.9       61.4
   42   3   0   5 30.223  60.445   0.327    5.68    4       46.7       32.0
   43   1   3   4 31.405  62.811   0.338    5.22    8       17.6        8.3
   44   2   3   3 31.453  62.907   0.339    5.2     8       10.7        3.1
   45   0   2   6 31.476  62.951   0.339    5.19    4       61.6       50.9
   46   4   1   3 31.69   63.379   0.341    5.11    8       25.5       17.1
   47   1   0   7 31.98   63.96    0.344    5.01    4       14.4        2.7
   48   4   2   0 32.196  64.392   0.346    4.94    4        8.4        0.9
   49   0   1   7 32.363  64.727   0.347    4.88    4        5.3        0.4
   50   4   0   4 32.907  65.814   0.353    4.71    4       45.4       25.1
   51   0   4   0 33.482  66.964   0.358    4.54    2      116.7       79.8
   52   4   2   2 33.568  67.136   0.359    4.52    8       51.5       61.9
   53   0   3   5 33.689  67.379   0.36     4.48    4       36.0       15.0
   54   3   3   2 33.828  67.657   0.361    4.45    8       20.6        9.8
   55   1   4   1 34.621  69.243   0.369    4.24    8       35.2       27.1
   56   2   2   6 34.73   69.461   0.37     4.21    8       38.4       32.0
   57   0   4   2 34.829  69.658   0.371    4.19    4       15.9        2.7
   58   3   2   5 35.029  70.057   0.373    4.14    8       58.3       72.7
   59   5   0   1 35.071  70.142   0.373    4.13    4       51.4       28.1
   60   3   1   6 35.211  70.421   0.374    4.09    8       39.3       32.7
   61   2   1   7 35.577  71.154   0.378    4.01    8       16.3        5.5
   62   0   0   8 36.235  72.471   0.384    3.87    2       55.2       15.2
   63   2   4   0 36.649  73.298   0.387    3.79    4       17.6        3.0
   64   1   2   7 36.666  73.332   0.388    3.78    8       30.8       18.5
   65   2   3   5 36.848  73.696   0.389    3.75    8       40.1       31.1
   66   4   1   5 37.067  74.135   0.391    3.71    8       25.5       12.4
   67   5   1   2 37.201  74.401   0.392    3.68    8       13.5        3.5
   68   1   4   3 37.255  74.511   0.393    3.67    8       38.2       27.7
   69   4   2   4 37.539  75.077   0.396    3.62    8       10.3        2.0
   70   5   0   3 37.692  75.384   0.397    3.6     4       31.5        9.2
   71   3   3   4 37.787  75.574   0.398    3.58    8       35.2       23.0
   72   2   4   2 37.947  75.893   0.399    3.55    8       18.8        6.5
   73   1   3   6 38.099  76.199   0.401    3.53    8        7.8        1.1
   74   1   1   8 38.14   76.28    0.401    3.52    8       14.4        3.8
   75   3   0   7 38.316  76.632   0.402    3.49    4        0.4        0.0
   76   4   3   1 38.32   76.639   0.402    3.49    8       22.1        8.8
   77   0   4   4 38.745  77.49    0.406    3.43    4       65.7       38.2
   78   2   0   8 39.311  78.621   0.411    3.35    4        4.5        0.2
   79   4   0   6 39.485  78.97    0.413    3.32    4       18.4        2.9
   80   5   2   1 39.596  79.192   0.414    3.31    8       24.6       10.3
   81   0   2   8 40.715  81.43    0.423    3.17    4       38.9       12.4
   82   3   4   1 40.785  81.57    0.424    3.16    8        1.5        0.0
   83   4   3   3 40.868  81.736   0.425    3.15    8       28.4       13.2
   84   5   1   4 41.038  82.075   0.426    3.13    8       16.6        4.4
   85   0   3   7 41.479  82.959   0.43     3.09    4       27.5        6.0
   86   2   4   4 41.764  83.529   0.432    3.06    8       11.2        2.0
   87   5   2   3 42.125  84.251   0.435    3.03    8       15.2        3.6
   88   1   4   5 42.35   84.701   0.437    3.01    8       46.3       33.4
   89   1   0   9 42.43   84.859   0.438    3.0     4       13.0        1.3
   90   3   2   7 42.734  85.467   0.44     2.97    8       41.6       26.6
   91   5   0   5 42.773  85.547   0.441    2.97    4       64.1       31.5
   92   0   1   9 42.777  85.553   0.441    2.97    4       28.8        6.4
   93   6   0   0 43.14   86.28    0.444    2.94    2       63.8       15.5
   94   3   4   3 43.301  86.603   0.445    2.93    8        8.6        1.1
   95   2   2   8 43.707  87.414   0.449    2.9     8       15.8        3.8
   96   4   2   6 43.878  87.757   0.45     2.89    8       65.3       63.7
   97   0   5   1 43.911  87.823   0.45     2.89    4       11.6        1.0
   98   3   3   6 44.119  88.238   0.452    2.88    8       17.6        4.6
   99   3   1   8 44.158  88.317   0.452    2.87    8       16.0        3.8
  100   6   0   2 44.392  88.785   0.454    2.86    4       39.4       11.5
  101   2   3   7 44.465  88.929   0.455    2.86    8       36.1       19.2
  102   6   1   1 44.544  89.088   0.455    2.85    8       37.5       20.7
  103   4   1   7 44.675  89.351   0.456    2.85    8       17.6        4.6


  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   1   0   1   7.806  15.612  5.67132     1523.5    100.0    100.0     5.6
    2   0   1   1   9.002  18.003  4.92303       20.1      1.3      1.3     5.6
    3   2   0   0  13.175  26.35   3.3795       172.2     11.3     11.2     5.6
    4   1   1   2  13.418  26.836  3.31946       79.1      5.2      5.2     5.6
    5   1   0   3  14.433  28.866  3.09047       67.9      4.5      4.4     5.6
    6   0   2   0  16.012  32.024  2.7925        73.2      4.8      4.7     5.6
    7   2   1   1  16.049  32.098  2.78619      883.4     58.0     57.3     5.6
    8   0   0   4  17.191  34.381  2.60625      272.3     17.9     17.6     5.7
    9   1   2   1  17.906  35.813  2.50527      233.5     15.3     15.1     5.7
   10   1   1   4  20.211  40.423  2.22956       28.9      1.9      1.9     5.7
   11   2   1   3  20.277  40.555  2.22261       49.3      3.2      3.2     5.7
   12   2   2   0  20.967  41.933  2.15268      328.0     21.5     21.1     5.7
   13   1   2   3  21.825  43.649  2.07195       41.0      2.7      2.6     5.7
   14   2   0   4  21.915  43.83   2.06382       28.6      1.9      1.8     5.7
   15   1   0   5  22.744  45.488  1.99236      231.4     15.2     14.8     5.7
   16   2   2   2  22.777  45.553  1.98968       28.6      1.9      1.8     5.7
   17   0   1   5  23.225  46.45   1.95332      114.2      7.5      7.3     5.7
   18   0   3   1  24.854  49.708  1.83267       30.3      2.0      1.9     5.7
   19   0   0   6  26.316  52.633  1.7375        22.9      1.5      1.5     5.8
   20   3   2   1  26.453  52.906  1.72917      299.8     19.7     19.0     5.8
   21   1   3   2  26.994  53.988  1.69704       61.2      4.0      3.9     5.8
   22   4   0   0  27.12   54.24   1.68975      172.4     11.3     10.9     5.8
   23   2   2   4  27.652  55.304  1.65973      251.8     16.5     15.9     5.8
   24   1   2   5  28.355  56.71   1.62188       46.6      3.1      2.9     5.8
   25   2   3   1  28.563  57.126  1.61103       32.3      2.1      2.0     5.8
   26   4   0   2  28.634  57.267  1.6074        16.4      1.1      1.0     5.8
   27   2   0   6  29.9    59.8    1.54524       61.4      4.0      3.9     5.8
   28   3   0   5  30.223  60.445  1.53027       32.0      2.1      2.0     5.8
   29   0   2   6  31.476  62.951  1.47525       54.0      3.5      3.4     5.9
   30   4   1   3  31.69   63.379  1.46631       17.1      1.1      1.1     5.9
   31   4   0   4  32.907  65.814  1.41783       25.1      1.6      1.6     5.9
   32   0   4   0  33.482  66.964  1.39625       79.8      5.2      5.0     5.9
   33   4   2   2  33.568  67.136  1.3931        61.9      4.1      3.8     5.9
   34   1   4   1  34.621  69.243  1.35577       27.1      1.8      1.7     5.9
   35   2   2   6  34.73   69.461  1.35204       32.0      2.1      2.0     5.9
   36   3   2   5  35.029  70.057  1.34198       72.7      4.8      4.5     5.9
   37   5   0   1  35.071  70.142  1.34058       28.1      1.8      1.7     5.9
   38   3   1   6  35.211  70.421  1.33594       32.7      2.1      2.0     5.9
   39   0   0   8  36.235  72.471  1.30312       15.2      1.0      0.9     5.9
   40   1   2   7  36.666  73.332  1.28993       21.5      1.4      1.3     6.0
   41   2   3   5  36.848  73.696  1.28446       31.1      2.0      1.9     6.0
   42   1   4   3  37.255  74.511  1.27242       27.7      1.8      1.7     6.0
   43   3   3   4  37.787  75.574  1.25713       23.0      1.5      1.4     6.0
   44   0   4   4  38.745  77.49   1.23076       38.2      2.5      2.3     6.0
   45   1   4   5  42.35   84.701  1.14342       33.4      2.2      2.0     6.1
   46   3   2   7  42.734  85.467  1.13512       26.6      1.7      1.6     6.1
   47   5   0   5  42.773  85.547  1.13426       37.9      2.5      2.3     6.1
   48   6   0   0  43.14   86.28   1.1265        15.5      1.0      0.9     6.1
   49   4   2   6  43.878  87.757  1.11131       63.7      4.2      3.8     6.2
   50   2   3   7  44.465  88.929  1.09966       19.2      1.3      1.1     6.2
   51   6   1   1  44.544  89.088  1.09812       20.7      1.4      1.2     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)