data_global
_chemical_name_mineral 'Ilvaite'
loop_
_publ_author_name
'Ghose S'
'Hewat A W'
'Marezio M'
_journal_name_full 'Physics and Chemistry of Minerals'
_journal_volume 11 
_journal_year 1984
_journal_page_first 67
_journal_page_last 74
_publ_section_title
;
 A neutron powder diffraction study of the crystal and
 magnetic structures of ilvaite from 305 K to 5 K - a mixed
 valence iron silicate with an electronic transition
 Sample: T = 5 K
;
_database_code_amcsd 0007361
_chemical_formula_sum 'Ca Fe2.925 Mn.075 Si2 O9 H'
_cell_length_a 13.0229
_cell_length_b 8.7977
_cell_length_c 5.8428
_cell_angle_alpha 90
_cell_angle_beta 90.234
_cell_angle_gamma 90
_cell_volume 669.413
_exptl_crystal_density_diffrn      4.056
_symmetry_space_group_name_H-M 'P 1 21/a 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2-y,z'
  '1/2-x,1/2+y,-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
Ca   0.81340   0.37050   0.73130   1.00000   0.02406
FeM11   0.88900   0.05540   0.01010   1.00000   0.00608
FeM12   0.88960   0.04700   0.49440   1.00000   0.00608
FeM2   0.94100   0.74380   0.24160   0.92500   0.00798
MnM2   0.94100   0.74380   0.24160   0.07500   0.00798
Si1   0.96490   0.36810   0.22230   1.00000   0.00709
Si2   0.67920   0.22910   0.25610   1.00000   0.00709
O1   0.01020   0.02850   0.73390   1.00000   0.01140
O21   0.93790   0.27310   0.01110   1.00000   0.01140
O22   0.93390   0.27250   0.48530   1.00000   0.01140
O5   0.58570   0.10300   0.26070   1.00000   0.01140
O6   0.60040   0.02600   0.75260   1.00000   0.01140
O3   0.77840   0.10860   0.26390   1.00000   0.01140
O41   0.66700   0.32800   0.01590   1.00000   0.01140
O42   0.67160   0.33680   0.47900   1.00000   0.01140
O7   0.79770   0.10510   0.73810   1.00000   0.01140
H   0.73360   0.06100   0.73860   1.00000   0.01874