data_global
_chemical_name_mineral 'Vermiculite'
loop_
_publ_author_name
'Mathieson A M'
'Walker G F'
_journal_name_full 'American Mineralogist'
_journal_volume 39 
_journal_year 1954
_journal_page_first 231
_journal_page_last 255
_publ_section_title
;
 Crystal structure of magnesium-vermiculite
;
_database_code_amcsd 0000063
_chemical_formula_sum 'Mg1.338 Fe.24 Al.721 Si1.36 O9 H3'
_cell_length_a 5.33
_cell_length_b 9.18
_cell_length_c 28.90
_cell_angle_alpha 90
_cell_angle_beta 97
_cell_angle_gamma 90
_cell_volume 1403.520
_exptl_crystal_density_diffrn      1.186
_symmetry_space_group_name_H-M 'C 1 c 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,1/2+z'
  '1/2+x,1/2-y,1/2+z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Mg1   0.00000   0.00000   0.00000   0.39300
Fe1   0.00000   0.00000   0.00000   0.08000
Al1   0.00000   0.00000   0.00000   0.02700
Mg2   0.00000   0.33300   0.00000   0.39300
Fe2   0.00000   0.33300   0.00000   0.08000
Al2   0.00000   0.33300   0.00000   0.02700
Mg3   0.00000   0.66700   0.00000   0.39300
Fe3   0.00000   0.66700   0.00000   0.08000
Al3   0.00000   0.66700   0.00000   0.02700
Si1   0.39700   0.00000   0.09600   0.68000
Al4   0.39700   0.00000   0.09600   0.32000
Si2   0.39700   0.33300   0.09700   0.68000
Al5   0.39700   0.33300   0.09700   0.32000
Mg4   0.50000   0.00000   0.25000   0.05300
Mg5   0.50000   0.33300   0.25000   0.05300
Mg6   0.50000   0.66700   0.25000   0.05300
O1   0.35800   0.00000   0.03700   1.00000
O2   0.35800   0.33300   0.03700   1.00000
O3   0.35800   0.66700   0.03700   1.00000
O4   0.14700   0.40400   0.11400   1.00000
O5   0.14700   0.92900   0.11400   1.00000
O6   0.43400   0.16700   0.11400   1.00000
O-H7   0.16000  -0.01900   0.21300   1.00000
O-H8   0.16000   0.35200   0.21300   1.00000
O-H9   0.10500   0.66700   0.21300   1.00000