The structure described by Ba8Bi10O27 crystallizes in the trigonal R-3 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 11-coordinate geometry to one O(5), two equivalent O(2), two equivalent O(3), three equivalent O(1), and three equivalent O(4) atoms. In the second Ba site, Ba(2) is bonded to three equivalent O(1), three equivalent O(3), three equivalent O(4), and three equivalent O(5) atoms to form BaO12 cuboctahedra that share corners with three equivalent Ba(2)O12 cuboctahedra,  a faceface with one Bi(1)O6 octahedra,  a faceface with one Bi(3)O6 octahedra, and faces with six equivalent Bi(2)O6 octahedra. There are four inequivalent Bi sites. In the first Bi site, Bi(4) is bonded in a 6-coordinate geometry to six equivalent O(2) atoms. In the second Bi site, Bi(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form BiO6 octahedra that share corners with six equivalent Bi(2)O6 octahedra and  a faceface with one Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 5-13°. In the third Bi site, Bi(2) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form BiO6 octahedra that share  a cornercorner with one Bi(3)O6 octahedra, corners with two equivalent Bi(1)O6 octahedra, corners with three equivalent Bi(2)O6 octahedra, and faces with two equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-13°. In the fourth Bi site, Bi(3) is bonded to six equivalent O(4) atoms to form BiO6 octahedra that share corners with six equivalent Bi(2)O6 octahedra and faces with two equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 7°. There are five inequivalent O sites. In the first O site, O(5) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Bi(2) atoms to form distorted corner-sharing OBa4Bi2 octahedra. The corner-sharing octahedral tilt angles are 60°. In the second O site, O(4) is bonded in a 6-coordinate geometry to one Ba(2), three equivalent Ba(1), one Bi(2), and one Bi(3) atom. In the third O site, O(1) is bonded in a 6-coordinate geometry to one Ba(2), three equivalent Ba(1), one Bi(1), and one Bi(2) atom. In the fourth O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Ba(1), one Bi(1), one Bi(2), and one Bi(4) atom. In the fifth O site, O(3) is bonded in a 2-coordinate geometry to one Ba(2), two equivalent Ba(1), and two equivalent Bi(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba8Bi10O27
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.891
_cell_length_b   9.891
_cell_length_c   9.891
_cell_angle_alpha   66.504
_cell_angle_beta   66.504
_cell_angle_gamma   66.504
_symmetry_Int_Tables_number   1
_cell_volume   780.066
_cell_formula_units_Z   1
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  0.889  0.218  0.573  1.0
  Ba  Ba1  1  0.335  0.335  0.335  1.0
  Ba  Ba2  1  0.427  0.111  0.782  1.0
  Ba  Ba3  1  0.782  0.427  0.111  1.0
  Ba  Ba4  1  0.218  0.573  0.889  1.0
  Ba  Ba5  1  0.665  0.665  0.665  1.0
  Ba  Ba6  1  0.111  0.782  0.427  1.0
  Ba  Ba7  1  0.573  0.889  0.218  1.0
  Bi  Bi8  1  0.166  0.166  0.166  1.0
  Bi  Bi9  1  0.724  0.056  0.388  1.0
  Bi  Bi10  1  0.612  0.276  0.944  1.0
  Bi  Bi11  1  0.056  0.388  0.724  1.0
  Bi  Bi12  1  0.500  0.500  0.500  1.0
  Bi  Bi13  1  0.388  0.724  0.056  1.0
  Bi  Bi14  1  0.944  0.612  0.276  1.0
  Bi  Bi15  1  0.834  0.834  0.834  1.0
  Bi  Bi16  1  0.276  0.944  0.612  1.0
  Bi  Bi17  1  0.000  0.000  0.000  1.0
  O  O18  1  0.396  0.210  0.053  1.0
  O  O19  1  0.945  0.106  0.254  1.0
  O  O20  1  0.210  0.053  0.396  1.0
  O  O21  1  0.680  0.160  0.160  1.0
  O  O22  1  0.746  0.055  0.894  1.0
  O  O23  1  0.160  0.160  0.680  1.0
  O  O24  1  0.616  0.285  0.429  1.0
  O  O25  1  0.053  0.396  0.210  1.0
  O  O26  1  0.840  0.320  0.840  1.0
  O  O27  1  0.106  0.254  0.945  1.0
  O  O28  1  0.160  0.680  0.160  1.0
  O  O29  1  0.571  0.384  0.715  1.0
  O  O30  1  0.000  0.500  0.500  1.0
  O  O31  1  0.429  0.616  0.285  1.0
  O  O32  1  0.285  0.429  0.616  1.0
  O  O33  1  0.715  0.571  0.384  1.0
  O  O34  1  0.894  0.746  0.055  1.0
  O  O35  1  0.840  0.840  0.320  1.0
  O  O36  1  0.384  0.715  0.571  1.0
  O  O37  1  0.254  0.945  0.106  1.0
  O  O38  1  0.500  0.500  0.000  1.0
  O  O39  1  0.947  0.604  0.790  1.0
  O  O40  1  0.500  0.000  0.500  1.0
  O  O41  1  0.320  0.840  0.840  1.0
  O  O42  1  0.790  0.947  0.604  1.0
  O  O43  1  0.604  0.790  0.947  1.0
  O  O44  1  0.055  0.894  0.746  1.0
[/CIF]
.
The structure described by Ba8Bi10O27 crystallizes in the trigonal R-3 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 11-coordinate geometry to one O(5), two equivalent O(2), two equivalent O(3), three equivalent O(1), and three equivalent O(4) atoms. In the second Ba site, Ba(2) is bonded to three equivalent O(1), three equivalent O(3), three equivalent O(4), and three equivalent O(5) atoms to form BaO12 cuboctahedra that share corners with three equivalent Ba(2)O12 cuboctahedra,  a faceface with one Bi(1)O6 octahedra,  a faceface with one Bi(3)O6 octahedra, and faces with six equivalent Bi(2)O6 octahedra. There are four inequivalent Bi sites. In the first Bi site, Bi(4) is bonded in a 6-coordinate geometry to six equivalent O(2) atoms. In the second Bi site, Bi(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form BiO6 octahedra that share corners with six equivalent Bi(2)O6 octahedra and  a faceface with one Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 5-13°. In the third Bi site, Bi(2) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form BiO6 octahedra that share  a cornercorner with one Bi(3)O6 octahedra, corners with two equivalent Bi(1)O6 octahedra, corners with three equivalent Bi(2)O6 octahedra, and faces with two equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-13°. In the fourth Bi site, Bi(3) is bonded to six equivalent O(4) atoms to form BiO6 octahedra that share corners with six equivalent Bi(2)O6 octahedra and faces with two equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 7°. There are five inequivalent O sites. In the first O site, O(5) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Bi(2) atoms to form distorted corner-sharing OBa4Bi2 octahedra. The corner-sharing octahedral tilt angles are 60°. In the second O site, O(4) is bonded in a 6-coordinate geometry to one Ba(2), three equivalent Ba(1), one Bi(2), and one Bi(3) atom. In the third O site, O(1) is bonded in a 6-coordinate geometry to one Ba(2), three equivalent Ba(1), one Bi(1), and one Bi(2) atom. In the fourth O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Ba(1), one Bi(1), one Bi(2), and one Bi(4) atom. In the fifth O site, O(3) is bonded in a 2-coordinate geometry to one Ba(2), two equivalent Ba(1), and two equivalent Bi(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba8Bi10O27
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.891
_cell_length_b   9.891
_cell_length_c   9.891
_cell_angle_alpha   66.504
_cell_angle_beta   66.504
_cell_angle_gamma   66.504
_symmetry_Int_Tables_number   1
_cell_volume   780.066
_cell_formula_units_Z   1
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  0.889  0.218  0.573  1.0
  Ba  Ba1  1  0.335  0.335  0.335  1.0
  Ba  Ba2  1  0.427  0.111  0.782  1.0
  Ba  Ba3  1  0.782  0.427  0.111  1.0
  Ba  Ba4  1  0.218  0.573  0.889  1.0
  Ba  Ba5  1  0.665  0.665  0.665  1.0
  Ba  Ba6  1  0.111  0.782  0.427  1.0
  Ba  Ba7  1  0.573  0.889  0.218  1.0
  Bi  Bi8  1  0.166  0.166  0.166  1.0
  Bi  Bi9  1  0.724  0.056  0.388  1.0
  Bi  Bi10  1  0.612  0.276  0.944  1.0
  Bi  Bi11  1  0.056  0.388  0.724  1.0
  Bi  Bi12  1  0.500  0.500  0.500  1.0
  Bi  Bi13  1  0.388  0.724  0.056  1.0
  Bi  Bi14  1  0.944  0.612  0.276  1.0
  Bi  Bi15  1  0.834  0.834  0.834  1.0
  Bi  Bi16  1  0.276  0.944  0.612  1.0
  Bi  Bi17  1  0.000  0.000  0.000  1.0
  O  O18  1  0.396  0.210  0.053  1.0
  O  O19  1  0.945  0.106  0.254  1.0
  O  O20  1  0.210  0.053  0.396  1.0
  O  O21  1  0.680  0.160  0.160  1.0
  O  O22  1  0.746  0.055  0.894  1.0
  O  O23  1  0.160  0.160  0.680  1.0
  O  O24  1  0.616  0.285  0.429  1.0
  O  O25  1  0.053  0.396  0.210  1.0
  O  O26  1  0.840  0.320  0.840  1.0
  O  O27  1  0.106  0.254  0.945  1.0
  O  O28  1  0.160  0.680  0.160  1.0
  O  O29  1  0.571  0.384  0.715  1.0
  O  O30  1  0.000  0.500  0.500  1.0
  O  O31  1  0.429  0.616  0.285  1.0
  O  O32  1  0.285  0.429  0.616  1.0
  O  O33  1  0.715  0.571  0.384  1.0
  O  O34  1  0.894  0.746  0.055  1.0
  O  O35  1  0.840  0.840  0.320  1.0
  O  O36  1  0.384  0.715  0.571  1.0
  O  O37  1  0.254  0.945  0.106  1.0
  O  O38  1  0.500  0.500  0.000  1.0
  O  O39  1  0.947  0.604  0.790  1.0
  O  O40  1  0.500  0.000  0.500  1.0
  O  O41  1  0.320  0.840  0.840  1.0
  O  O42  1  0.790  0.947  0.604  1.0
  O  O43  1  0.604  0.790  0.947  1.0
  O  O44  1  0.055  0.894  0.746  1.0
[/CIF]
.