data_9009253
_chemical_name 'Benstonite'
loop_
_publ_author_name
'Effenberger H'
_journal_name_full "Neues Jahrbuch fur Mineralogie, Abhandlungen"
_journal_volume 136
_journal_year 1979
_journal_page_first 326
_journal_page_last 337
_publ_section_title
;
 Kristallstruktur und chemische formel des benstonits, Ba6Ca6Mg(CO3)13
;
_chemical_formula_sum 'Ba6 Ca6 Mg O39 C13'
_cell_length_a 18.280
_cell_length_b 18.280
_cell_length_c 8.652
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 2503.799
_symmetry_space_group_name_H-M 'R -3'
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '2/3+x,1/3+y,1/3+z'
  '1/3+x,2/3+y,2/3+z'
  'y,-x+y,-z'
  '2/3+y,1/3-x+y,1/3-z'
  '1/3+y,2/3-x+y,2/3-z'
  '-x+y,-x,z'
  '2/3-x+y,1/3-x,1/3+z'
  '1/3-x+y,2/3-x,2/3+z'
  '-x,-y,-z'
  '2/3-x,1/3-y,1/3-z'
  '1/3-x,2/3-y,2/3-z'
  '-y,x-y,z'
  '2/3-y,1/3+x-y,1/3+z'
  '1/3-y,2/3+x-y,2/3+z'
  'x-y,x,-z'
  '2/3+x-y,1/3+x,1/3-z'
  '1/3+x-y,2/3+x,2/3-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_Uiso_or_equiv
Ba   0.05330   0.17780   0.30070   1.00000 ?
Ca   0.33190   0.08600   0.02380   1.00000 ?
Mg   0.00000   0.00000   0.00000   1.00000   0.00700
O1   0.48200   0.48560   0.17240   1.00000   0.01900
O2   0.37980   0.35430   0.11800   1.00000   0.01300
O3   0.35250   0.46130   0.11850   1.00000   0.01500
O4   0.23930   0.11240   0.18170   1.00000   0.01000
O5   0.10390   0.06890   0.14140   1.00000   0.02700
O6   0.19930   0.20360   0.11010   1.00000   0.02000
O7   0.07890   0.05490   0.47490   0.50000   0.01800
C1   0.40580   0.43340   0.13980   1.00000   0.00900
C2   0.17970   0.12880   0.13760   1.00000   0.00800
C3   0.00000   0.00000   0.47850   0.50000   0.01700