Ilimaussite-(Ce)
Ferraris G, Gula A, Zubkova N V, Pushcharovsky D Y,
Gobetchiya E R, Pekov I V, Eldjarn K
The Canadian Mineralogist 42 (2004) 787-795
The crystal structure of ilimaussite-(Ce),
(Ba,Na)10K3Na4.5Ce5(Nb,Ti)[Si12O36][Si9O18(O,OH)24]O6,
and the "ilimaussite" problem
_database_code_amcsd 0005939
10.770 10.770 61.05 90 90 120 R32
atom     x     y       z occ Uiso
Ce1    2/3   1/3 -.00005 .85 .027
Fe1    2/3   1/3 -.00005 .15 .027
Ce2    1/3 .0005     1/6 2/3 .048
Fe2    1/3 .0005     1/6 1/3 .048
Ba1  .0005 .3263   .1001 2/3 .044
Na1  .0005 .3263   .1001 .22 .044
K1   .0005 .3263   .1001 .12 .044
Ba2    1/3   2/3   .0657 .85 .043
Th2    1/3   2/3   .0657 .15 .043
Ba3    2/3   1/3  .06561 .95 .037
K3     2/3   1/3  .06561 .05 .037
Nb   .3439 .3427   .0844 .62 .038
Ti   .3439 .3427   .0844 .33 .038
Fe   .3439 .3427   .0844 .05 .038
Na1   .489  .485   .0277  .5 .015
Na2   .505  .505       0  .5  .05
K1       0     0   .0728  .9 .029
Ba1      0     0   .0728  .1 .029
K2       0     0       0  .8 .042
Sr2      0     0       0  .1 .042
Ba2      0     0       0  .1 .042
Si1  .3254  .168   .0386     .026
Si2  .1562 .8297   .0387     .021
Si3   .168  .167   .1302  .5 .016
Si4   .333  .502   .1292  .5 .017
Si5   .505  .331   .1292  .5 .018
O1    .332  .175   .0670     .030
O2    .486  .489   .0678     .041
O3    .157  .822   .0673     .033
O4    .175  .183   .1032     .037
O5    .328  .473   .1022     .045
O6    .486  .333   .1023     .040
O7    .216 -.000   .0300     .039
O8    .478  .220   .0267     .034
O9    .264  .783   .0270      .03
O10   .270  .273   .0281     .029
OH11   2/3   1/3   .1290      .10
OH12 .3439 .1962   .1390      .10
OH13 .4768 .4690   .1360      .10
OH14 .2077 .3422   .1380      .10
OH15     0     0   .1290      .15
OH16   1/6   1/3   .1290      .15