data_global
_chemical_name_mineral 'Cordierite'
loop_
_publ_author_name
'Koepke J'
'Schulz H'
_journal_name_full 'Physics and Chemistry of Minerals'
_journal_volume 13 
_journal_year 1986
_journal_page_first 165
_journal_page_last 173
_publ_section_title
;
 Single crystal structure investigations under high-pressure of the
 mineral cordierite with an improved high-pressure cell
 Sample: P = 2.2 GPa
;
_database_code_amcsd 0007388
_chemical_compound_source 'Zabargad island, Red Sea'
_chemical_formula_sum 'Mg2 Al4 Si5 O18'
_cell_length_a 16.975
_cell_length_b 9.647
_cell_length_c 9.274
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 1518.690
_exptl_crystal_density_diffrn      2.558
_symmetry_space_group_name_H-M 'C c c m'
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'
  '-x,y,1/2-z'
  '1/2-x,1/2+y,1/2-z'
  '-x,y,1/2+z'
  '1/2-x,1/2+y,1/2+z'
  'x,-y,1/2-z'
  '1/2+x,1/2-y,1/2-z'
  'x,y,-z'
  '1/2+x,1/2+y,-z'
  '-x,-y,z'
  '1/2-x,1/2-y,z'
  '-x,-y,-z'
  '1/2-x,1/2-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Mg   0.16220   0.50000   0.25000   0.00740
Al11   0.25000   0.25000   0.24730   0.00760
Si16   0.00000   0.50000   0.25000   0.00320
Si21   0.19380   0.07700   0.00000   0.00630
Al26   0.05200   0.30550   0.00000   0.00690
Si23  -0.13480   0.23690   0.00000   0.00110
O11   0.24730   0.10330   0.14260   0.00580
O16   0.06250   0.41520   0.15020   0.00650
O13  -0.17340   0.31270   0.14140   0.00550
O21   0.12270   0.18330   0.00000   0.00500
O26  -0.04300   0.24410   0.00000   0.01820
O23  -0.16460   0.08120   0.00000   0.00980