data_global
_chemical_name_mineral 'Sepiolite'
loop_
_publ_author_name
'Giustetto R'
'Levy D'
'Wahyudi O'
'Ricchiardi G'
'Vitillo J G'
_journal_name_full 'European Journal of Mineralogy'
_journal_volume 23 
_journal_year 2011
_journal_page_first 449
_journal_page_last 466
_publ_section_title
;
 Crystal structure refinement of a sepiolite/indigo Maya Blue pigment
 using molecular modelling and synchrotron diffraction
;
_database_code_amcsd 0018363
_chemical_compound_source 'Germany'
_chemical_formula_sum 'Mg4 Si6 O22.82 H13.64'
_cell_length_a 13.395
_cell_length_b 27.016
_cell_length_c 5.2765
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 1909.456
_exptl_crystal_density_diffrn      2.242
_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
_atom_site_occupancy
_atom_site_U_iso_or_equiv
Mg1   0.00000   0.02900   0.25000   1.00000   0.02900
Mg2   0.00000   0.08400   0.75000   1.00000   0.02900
Mg3   0.00000   0.14590   0.25000   1.00000   0.02900
Mg4   0.00000   0.20400   0.75000   1.00000   0.02900
Si1   0.20000   0.02740   0.59100   1.00000   0.01100
Si2   0.21100   0.14070   0.57700   1.00000   0.01100
Si3   0.20400   0.19480   0.06200   1.00000   0.01100
O1   0.07600   0.03000   0.60200   1.00000   0.01400
O-H2   0.07600   0.08900   0.05500   1.00000   0.01400
O3   0.09000   0.14530   0.55500   1.00000   0.01400
O4   0.07800   0.19300   0.06700   1.00000   0.01400
O5   0.24800   0.00260   0.33300   1.00000   0.01400
O6   0.24400   0.08330   0.60000   1.00000   0.01400
O7   0.24300   0.16500   0.30800   1.00000   0.01400
O8   0.25500   0.17200   0.80600   1.00000   0.01400
O9   0.25000   0.25000   0.07600   1.00000   0.01400
Wat10   0.10600   0.25270   0.58100   0.98000   0.02600
Wat11   0.56300  -0.10200   0.03200   0.73000   0.08000
Wat12   0.50000   0.18600   0.25000   0.92000   0.08000
Wat13   0.50000   0.04000   0.25000   0.96000   0.08000
Wat14   0.53000   0.16800   0.66000   0.26000   0.08000