data_global
_chemical_name_mineral 'Sepiolite'
loop_
_publ_author_name
'Brauner K'
'Preisinger A'
_journal_name_full 'Tschermaks Mineralogische und Petrographische Mitteilungen'
_journal_volume 6 
_journal_year 1956
_journal_page_first 120
_journal_page_last 140
_publ_section_title
;
 Struktur und entstehung des sepioliths
;
_database_code_amcsd 0015633
_chemical_formula_sum 'Mg4 Si6 O23 H14'
_cell_length_a 13.4
_cell_length_b 26.79999
_cell_length_c 5.28
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 1896.153
_exptl_crystal_density_diffrn      2.269
_symmetry_space_group_name_H-M 'P n c n'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2-x,1/2+y,1/2+z'
  '1/2+x,1/2-y,1/2-z'
  '1/2+x,1/2+y,-z'
  '1/2-x,1/2-y,z'
  'x,-y,1/2+z'
  '-x,y,1/2-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Mg1   0.00000   0.02800   0.25000
Mg2   0.00000   0.91600   0.25000
Mg3   0.00000   0.14000   0.25000
Mg4   0.00000   0.80400   0.25000
Si1   0.20800   0.02800   0.56250
Si2   0.20800   0.14000   0.56250
Si3   0.20800   0.19600   0.06250
O1   0.25000   0.25000   0.06250
O2   0.08400   0.02800   0.56250
O3   0.08400   0.14000   0.56250
O4   0.08400   0.19600   0.06250
O5   0.24000   0.00000   0.31250
O6   0.24000   0.08400   0.56250
O7   0.24000   0.16800   0.31250
O8   0.24000   0.16800   0.81250
O-H   0.08400   0.08400   0.06250
Wat1   0.08300   0.25000   0.50000
Wat2   0.08300   0.41600   0.91670
Wat3   0.00000   0.67200   0.25000
Wat4   0.00000   0.48500   0.25000