Vermiculite
Mathieson A M, Walker G F
American Mineralogist 39 (1954) 231-255
Crystal structure of magnesium-vermiculite
_database_code_amcsd 0000063
5.33 9.18 28.90 90 97 90 Cc
atom    x     y    z  occ
Mg1     0     0    0 .393
Fe1     0     0    0 .080
Al1     0     0    0 .027
Mg2     0 .3330    0 .393
Fe2     0 .3330    0 .080
Al2     0 .3330    0 .027
Mg3     0 .6670    0 .393
Fe3     0 .6670    0 .080
Al3     0 .6670    0 .027
Si1  .397     0 .096 .680
Al4  .397     0 .096 .320
Si2  .397 .3330 .097 .680
Al5  .397 .3330 .097 .320
Mg4    .5     0  .25 .053
Mg5    .5 .3330  .25 .053
Mg6    .5 .6670  .25 .053
O1   .358     0 .037
O2   .358 .3330 .037
O3   .358 .6670 .037
O4   .147 .4040 .114
O5   .147 .9290 .114
O6   .434 .1670 .114
OH7  .160 -.019 .213
OH8  .160 .3520 .213
OH9  .105 .6670 .213