The crystal structure described by Ba2Bi2Se3O2 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 3-coordinate geometry to one Se(1), four equivalent Se(2), and three equivalent O(1) atoms. Bi(1) is bonded in a distorted single-bond geometry to two equivalent Se(1), two equivalent Se(2), and one O(1) atom. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ba(1) and four equivalent Bi(1) atoms to form SeBa2Bi4 octahedra that share corners with two equivalent O(1)Ba3Bi tetrahedra, edges with two equivalent Se(1)Ba2Bi4 octahedra, and edges with four equivalent O(1)Ba3Bi tetrahedra. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to four equivalent Ba(1) and two equivalent Bi(1) atoms. O(1) is bonded to three equivalent Ba(1) and one Bi(1) atom to form OBa3Bi tetrahedra that share  a cornercorner with one Se(1)Ba2Bi4 octahedra, corners with two equivalent O(1)Ba3Bi tetrahedra, edges with two equivalent Se(1)Ba2Bi4 octahedra, and edges with two equivalent O(1)Ba3Bi tetrahedra. The corner-sharing octahedral tilt angles are 51°. is represented by the CIF file [CIF]
data_Ba2Bi2Se3O2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.231
_cell_length_b   10.115
_cell_length_c   11.902
_cell_angle_alpha   99.784
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   501.878
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ba  Ba0  1  0.491  0.705  0.598  1.0
  Ba  Ba1  1  0.991  0.795  0.902  1.0
  Ba  Ba2  1  0.509  0.295  0.402  1.0
  Ba  Ba3  1  0.009  0.205  0.098  1.0
  Bi  Bi4  1  0.495  0.451  0.813  1.0
  Bi  Bi5  1  0.995  0.049  0.687  1.0
  Bi  Bi6  1  0.505  0.549  0.187  1.0
  Bi  Bi7  1  0.005  0.951  0.313  1.0
  Se  Se8  1  0.500  0.000  0.500  1.0
  Se  Se9  1  0.000  0.500  0.000  1.0
  Se  Se10  1  0.497  0.087  0.859  1.0
  Se  Se11  1  0.997  0.413  0.641  1.0
  Se  Se12  1  0.503  0.913  0.141  1.0
  Se  Se13  1  0.003  0.587  0.359  1.0
  O  O14  1  0.506  0.339  0.186  1.0
  O  O15  1  0.006  0.161  0.314  1.0
  O  O16  1  0.494  0.661  0.814  1.0
  O  O17  1  0.994  0.839  0.686  1.0
[/CIF]
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The crystal structure described by Ba2Bi2Se3O2 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 3-coordinate geometry to one Se(1), four equivalent Se(2), and three equivalent O(1) atoms. Bi(1) is bonded in a distorted single-bond geometry to two equivalent Se(1), two equivalent Se(2), and one O(1) atom. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ba(1) and four equivalent Bi(1) atoms to form SeBa2Bi4 octahedra that share corners with two equivalent O(1)Ba3Bi tetrahedra, edges with two equivalent Se(1)Ba2Bi4 octahedra, and edges with four equivalent O(1)Ba3Bi tetrahedra. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to four equivalent Ba(1) and two equivalent Bi(1) atoms. O(1) is bonded to three equivalent Ba(1) and one Bi(1) atom to form OBa3Bi tetrahedra that share  a cornercorner with one Se(1)Ba2Bi4 octahedra, corners with two equivalent O(1)Ba3Bi tetrahedra, edges with two equivalent Se(1)Ba2Bi4 octahedra, and edges with two equivalent O(1)Ba3Bi tetrahedra. The corner-sharing octahedral tilt angles are 51°. is represented by the CIF file [CIF]
data_Ba2Bi2Se3O2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.231
_cell_length_b   10.115
_cell_length_c   11.902
_cell_angle_alpha   99.784
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   501.878
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ba  Ba0  1  0.491  0.705  0.598  1.0
  Ba  Ba1  1  0.991  0.795  0.902  1.0
  Ba  Ba2  1  0.509  0.295  0.402  1.0
  Ba  Ba3  1  0.009  0.205  0.098  1.0
  Bi  Bi4  1  0.495  0.451  0.813  1.0
  Bi  Bi5  1  0.995  0.049  0.687  1.0
  Bi  Bi6  1  0.505  0.549  0.187  1.0
  Bi  Bi7  1  0.005  0.951  0.313  1.0
  Se  Se8  1  0.500  0.000  0.500  1.0
  Se  Se9  1  0.000  0.500  0.000  1.0
  Se  Se10  1  0.497  0.087  0.859  1.0
  Se  Se11  1  0.997  0.413  0.641  1.0
  Se  Se12  1  0.503  0.913  0.141  1.0
  Se  Se13  1  0.003  0.587  0.359  1.0
  O  O14  1  0.506  0.339  0.186  1.0
  O  O15  1  0.006  0.161  0.314  1.0
  O  O16  1  0.494  0.661  0.814  1.0
  O  O17  1  0.994  0.839  0.686  1.0
[/CIF]
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