data_global
_chemical_name_mineral 'Braunite'
loop_
_publ_author_name
'Miletich R'
'Allan D R'
'Angel R J'
_journal_name_full 'Physics and Chemistry of Minerals'
_journal_volume 25 
_journal_year 1998
_journal_page_first 183
_journal_page_last 192
_publ_section_title
;
 Structural control of polyhedral compression in synthetic braunite,
 Mn2+Mn3+6O8SiO4
 Sample in air: P = 0.0001 GPa
;
_database_code_amcsd 0008123
_chemical_formula_sum 'Mn7 Si O12'
_cell_length_a 9.4264
_cell_length_b 9.4264
_cell_length_c 18.6962
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 1661.289
_exptl_crystal_density_diffrn      4.835
_symmetry_space_group_name_H-M 'I 41/a c d'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,1/2+z'
  '1/4-y,3/4-x,3/4+z'
  '3/4-y,1/4-x,1/4+z'
  '1/4+y,3/4+x,3/4-z'
  '3/4+y,1/4+x,1/4-z'
  '1/4+y,3/4-x,1/4-z'
  '3/4+y,1/4-x,3/4-z'
  '1/4-y,3/4+x,1/4+z'
  '3/4-y,1/4+x,3/4+z'
  '1/2+x,-y,z'
  '+x,1/2-y,1/2+z'
  '1/2-x,y,-z'
  '-x,1/2+y,1/2-z'
  '1/2+x,y,1/2-z'
  '+x,1/2+y,-z'
  '1/2-x,-y,1/2+z'
  '-x,1/2-y,+z'
  '1/4+y,1/4+x,1/4+z'
  '3/4+y,3/4+x,3/4+z'
  '1/4-y,1/4-x,1/4-z'
  '3/4-y,3/4-x,3/4-z'
  '1/4-y,1/4+x,3/4-z'
  '3/4-y,3/4+x,1/4-z'
  '1/4+y,1/4-x,3/4+z'
  '3/4+y,3/4-x,1/4+z'
  '-x,y,1/2+z'
  '1/2-x,1/2+y,+z'
  'x,-y,1/2-z'
  '1/2+x,1/2-y,-z'
  '-x,-y,-z'
  '1/2-x,1/2-y,1/2-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Mn1   0.00000   0.25000   0.12500   0.01381
Mn2   0.00000   0.00000   0.00000   0.01001
Mn3   0.25000   0.21663   0.00000   0.01001
Mn4   0.23282   0.48282   0.12500   0.00975
Si   0.00000   0.25000   0.37500   0.00887
O1   0.15074   0.85526   0.94565   0.01254
O2   0.14441   0.07326   0.05673   0.01229
O3   0.07780   0.13403   0.92521   0.01305
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
Mn1 0.01422 0.01422 0.01310 -0.00518 0.00000 0.00000
Mn2 0.00959 0.00990 0.01045 -0.00135 -0.00098 0.00045
Mn3 0.00950 0.00927 0.01116 0.00000 0.00071 0.00000
Mn4 0.00932 0.00932 0.01045 -0.00050 0.00027 0.00027
Si 0.00765 0.00765 0.01116 0.00000 0.00000 0.00000
O1 0.01188 0.01121 0.01434 -0.00081 -0.00045 0.00179
O2 0.01175 0.01274 0.01240 -0.00095 -0.00107 0.00045
O3 0.01098 0.01440 0.01364 0.00122 -0.00027 0.00161