The material described by Bi2MgO4 crystallizes in the orthorhombic Pmmn space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form distorted MgO6 pentagonal pyramids that share edges with four equivalent Bi(2)O6 octahedra. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(3) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), and four equivalent O(3) atoms. In the second Bi site, Bi(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form BiO6 octahedra that share edges with two equivalent Bi(2)O6 octahedra and edges with two equivalent Mg(1)O6 pentagonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Bi(1), and two equivalent Bi(2) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(2), one Bi(1), and two equivalent Bi(2) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), one Mg(2), one Bi(2), and two equivalent Bi(1) atoms. is represented by the CIF card [CIF]
data_Mg(BiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.100
_cell_length_b   6.841
_cell_length_c   11.313
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   472.143
_cell_formula_units_Z   4
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
  Mg  Mg0  1  0.860  0.000  0.500  1.0
  Mg  Mg1  1  0.140  0.500  0.000  1.0
  Mg  Mg2  1  0.535  0.000  0.000  1.0
  Mg  Mg3  1  0.465  0.500  0.500  1.0
  Bi  Bi4  1  0.506  0.500  0.209  1.0
  Bi  Bi5  1  0.506  0.500  0.791  1.0
  Bi  Bi6  1  0.494  0.000  0.291  1.0
  Bi  Bi7  1  0.494  0.000  0.709  1.0
  Bi  Bi8  1  0.000  0.250  0.250  1.0
  Bi  Bi9  1  0.000  0.750  0.750  1.0
  Bi  Bi10  1  0.000  0.750  0.250  1.0
  Bi  Bi11  1  0.000  0.250  0.750  1.0
  O  O12  1  0.902  0.500  0.125  1.0
  O  O13  1  0.902  0.500  0.875  1.0
  O  O14  1  0.098  0.000  0.375  1.0
  O  O15  1  0.098  0.000  0.625  1.0
  O  O16  1  0.249  0.500  0.354  1.0
  O  O17  1  0.249  0.500  0.646  1.0
  O  O18  1  0.751  0.000  0.146  1.0
  O  O19  1  0.751  0.000  0.854  1.0
  O  O20  1  0.678  0.237  0.379  1.0
  O  O21  1  0.678  0.763  0.621  1.0
  O  O22  1  0.322  0.737  0.121  1.0
  O  O23  1  0.322  0.263  0.879  1.0
  O  O24  1  0.322  0.263  0.121  1.0
  O  O25  1  0.322  0.737  0.879  1.0
  O  O26  1  0.678  0.763  0.379  1.0
  O  O27  1  0.678  0.237  0.621  1.0
[/CIF]
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The material described by Bi2MgO4 crystallizes in the orthorhombic Pmmn space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form distorted MgO6 pentagonal pyramids that share edges with four equivalent Bi(2)O6 octahedra. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(3) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), and four equivalent O(3) atoms. In the second Bi site, Bi(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form BiO6 octahedra that share edges with two equivalent Bi(2)O6 octahedra and edges with two equivalent Mg(1)O6 pentagonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Bi(1), and two equivalent Bi(2) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(2), one Bi(1), and two equivalent Bi(2) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), one Mg(2), one Bi(2), and two equivalent Bi(1) atoms. is represented by the CIF card [CIF]
data_Mg(BiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.100
_cell_length_b   6.841
_cell_length_c   11.313
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   472.143
_cell_formula_units_Z   4
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
  Mg  Mg0  1  0.860  0.000  0.500  1.0
  Mg  Mg1  1  0.140  0.500  0.000  1.0
  Mg  Mg2  1  0.535  0.000  0.000  1.0
  Mg  Mg3  1  0.465  0.500  0.500  1.0
  Bi  Bi4  1  0.506  0.500  0.209  1.0
  Bi  Bi5  1  0.506  0.500  0.791  1.0
  Bi  Bi6  1  0.494  0.000  0.291  1.0
  Bi  Bi7  1  0.494  0.000  0.709  1.0
  Bi  Bi8  1  0.000  0.250  0.250  1.0
  Bi  Bi9  1  0.000  0.750  0.750  1.0
  Bi  Bi10  1  0.000  0.750  0.250  1.0
  Bi  Bi11  1  0.000  0.250  0.750  1.0
  O  O12  1  0.902  0.500  0.125  1.0
  O  O13  1  0.902  0.500  0.875  1.0
  O  O14  1  0.098  0.000  0.375  1.0
  O  O15  1  0.098  0.000  0.625  1.0
  O  O16  1  0.249  0.500  0.354  1.0
  O  O17  1  0.249  0.500  0.646  1.0
  O  O18  1  0.751  0.000  0.146  1.0
  O  O19  1  0.751  0.000  0.854  1.0
  O  O20  1  0.678  0.237  0.379  1.0
  O  O21  1  0.678  0.763  0.621  1.0
  O  O22  1  0.322  0.737  0.121  1.0
  O  O23  1  0.322  0.263  0.879  1.0
  O  O24  1  0.322  0.263  0.121  1.0
  O  O25  1  0.322  0.737  0.879  1.0
  O  O26  1  0.678  0.763  0.379  1.0
  O  O27  1  0.678  0.237  0.621  1.0
[/CIF]
.