data_9000774
_chemical_name 'Braunite'
loop_
_publ_author_name
'de Villiers J P R'
_journal_name_full "American Mineralogist"
_journal_volume 65
_journal_year 1980
_journal_page_first 756
_journal_page_last 765
_publ_section_title
;
 The crystal structure of braunite II and its relation to bixbyite and braunite
;
_chemical_formula_sum '(Mn11.62 Fe2.38) Si O24'
_cell_length_a 9.431
_cell_length_b 9.431
_cell_length_c 37.774
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 3359.761
_symmetry_space_group_name_H-M 'I 41/a c d'
loop_
_symmetry_equiv_pos_as_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_occupancy
Mn1   0.00000   0.25000  -0.00918   0.83000
Fe1   0.00000   0.25000  -0.00918   0.17000
Mn2   0.20970   0.00000   0.25000   0.83000
Fe2   0.20970   0.00000   0.25000   0.17000
Mn3   0.24080   0.49080   0.12500   0.83000
Fe3   0.24080   0.49080   0.12500   0.17000
Mn4   0.03120   0.00060   0.06290   0.83000
Fe4   0.03120   0.00060   0.06290   0.17000
Mn5  -0.00960   0.00440   0.18772   0.83000
Fe5  -0.00960   0.00440   0.18772   0.17000
Si   0.00000   0.25000   0.37500   1.00000
O1   0.11970   0.17150   0.02560   1.00000
O2   0.33140   0.40100   0.03110   1.00000
O3   0.39820   0.12270   0.04120   1.00000
O4   0.11780   0.40710   0.08970   1.00000
O5   0.17010   0.11210   0.09090   1.00000
O6   0.38740   0.33610   0.10040   1.00000