data_global
_chemical_name_mineral 'Illite'
loop_
_publ_author_name
'Gualtieri A F'
_journal_name_full 'Journal of Applied Crystallography'
_journal_volume 33 
_journal_year 2000
_journal_page_first 267
_journal_page_last 278
_publ_section_title
;
 Accuracy of XRPD QPA using the combined Rietveld-RIR method
;
_database_code_amcsd 0012865
_chemical_compound_source 'Napoli, Italy'
_chemical_formula_sum 'K Al4 Si2 O12'
_cell_length_a 5.2226
_cell_length_b 9.0183
_cell_length_c 20.143
_cell_angle_alpha 90
_cell_angle_beta 95.665
_cell_angle_gamma 90
_cell_volume 944.081
_exptl_crystal_density_diffrn      2.780
_symmetry_space_group_name_H-M 'C 1 2/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'
  '-x,y,1/2-z'
  '1/2-x,1/2+y,1/2-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
K   0.00000   0.09010   0.25000   0.07500
Al1   0.44320   0.26350   0.13650   0.01100
Al2   0.25860   0.08280   0.00680   0.02700
Si   0.48250   0.92970   0.13700   0.02200
O1   0.46230   0.91940   0.05050   0.01500
O2   0.38350   0.26650   0.06630   0.04700
O3   0.42590   0.10390   0.15300   0.01200
O4   0.22260   0.83680   0.16850   0.04100
O5   0.27350   0.37220   0.16780   0.08000
O6   0.40800   0.56710   0.04540   0.05300