data_global
_chemical_name_mineral 'Tuhualite'
loop_
_publ_author_name
'Merlino S'
_journal_name_full 'Science'
_journal_volume 166 
_journal_year 1969
_journal_page_first 1399
_journal_page_last 1401
_publ_section_title
;
 Tuhualite crystal structure
 Note: Position of H2O not determined in paper
;
_database_code_amcsd 0015420
_chemical_compound_source 'Mayor Island, New Zealand'
_chemical_formula_sum 'Fe2 Si6 O15 Na'
_cell_length_a 14.31
_cell_length_b 17.28
_cell_length_c 10.11
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 2499.969
_exptl_crystal_density_diffrn      2.886
_symmetry_space_group_name_H-M 'C m c a'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,1/2-y,1/2+z'
  '1/2+x,-y,1/2+z'
  '-x,1/2+y,1/2-z'
  '1/2-x,+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,1/2+y,1/2-z'
  '1/2+x,+y,1/2-z'
  '-x,1/2-y,1/2+z'
  '1/2-x,-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
Fe1   0.24840   0.00000   0.00000   0.01393
Fe2   0.25000  -0.09450   0.25000   0.00633
Si1   0.39060   0.13210   0.01180   0.00887
Si2   0.38940   0.07040   0.30600   0.00760
Si3   0.39020   0.18940   0.54340   0.00633
O1   0.36920   0.22460  -0.00940   0.01393
O2   0.32980   0.07970  -0.08760   0.00507
O3   0.36430   0.11050   0.16190   0.01900
O4   0.32950  -0.00510   0.33700   0.00507
O5   0.36390   0.13580   0.41070   0.01393
O6   0.32920   0.17100   0.66740   0.01140
O7   0.50000   0.11300  -0.00900   0.01267
O8   0.50000   0.05320   0.30680   0.01646
O9   0.50000   0.17900   0.57920   0.02280
Na   0.25000   0.21970   0.25000   0.02280