The material structure described by Ba2Mg(NiO3)2 crystallizes in the hexagonal P-6m2 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent Mg(1) and six equivalent O(2) atoms to form distorted BaMg2O6 hexagonal bipyramids that share corners with eight equivalent Ba(1)Mg2O6 hexagonal bipyramids, edges with six equivalent Ba(2)O12 cuboctahedra, and edges with six equivalent Ni(1)O6 octahedra. In the second Ba site, Ba(2) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Ba(2)O12 cuboctahedra, corners with six equivalent Ni(1)O6 octahedra, edges with six equivalent Ba(1)Mg2O6 hexagonal bipyramids, faces with two equivalent Ba(2)O12 cuboctahedra, and faces with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 15°. Mg(1) is bonded in a trigonal planar geometry to two equivalent Ba(1) and three equivalent O(1) atoms. Ni(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NiO6 octahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, edges with three equivalent Ba(1)Mg2O6 hexagonal bipyramids, faces with three equivalent Ba(2)O12 cuboctahedra, and faces with two equivalent Ni(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Ba(2), one Mg(1), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Ni(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2Mg(NiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.770
_cell_length_b   5.770
_cell_length_c   5.579
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   160.853
_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  0.667  0.333  0.250  1.0
  Ba  Ba1  1  0.333  0.667  0.750  1.0
  Mg  Mg2  1  0.667  0.333  0.750  1.0
  Ni  Ni3  1  0.000  0.000  0.495  1.0
  Ni  Ni4  1  0.000  0.000  0.005  1.0
  O  O5  1  0.849  0.698  0.750  1.0
  O  O6  1  0.152  0.848  0.250  1.0
  O  O7  1  0.697  0.848  0.250  1.0
  O  O8  1  0.302  0.151  0.750  1.0
  O  O9  1  0.152  0.303  0.250  1.0
  O  O10  1  0.849  0.151  0.750  1.0
[/CIF]
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The material structure described by Ba2Mg(NiO3)2 crystallizes in the hexagonal P-6m2 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent Mg(1) and six equivalent O(2) atoms to form distorted BaMg2O6 hexagonal bipyramids that share corners with eight equivalent Ba(1)Mg2O6 hexagonal bipyramids, edges with six equivalent Ba(2)O12 cuboctahedra, and edges with six equivalent Ni(1)O6 octahedra. In the second Ba site, Ba(2) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Ba(2)O12 cuboctahedra, corners with six equivalent Ni(1)O6 octahedra, edges with six equivalent Ba(1)Mg2O6 hexagonal bipyramids, faces with two equivalent Ba(2)O12 cuboctahedra, and faces with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 15°. Mg(1) is bonded in a trigonal planar geometry to two equivalent Ba(1) and three equivalent O(1) atoms. Ni(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NiO6 octahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, edges with three equivalent Ba(1)Mg2O6 hexagonal bipyramids, faces with three equivalent Ba(2)O12 cuboctahedra, and faces with two equivalent Ni(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Ba(2), one Mg(1), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Ni(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2Mg(NiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.770
_cell_length_b   5.770
_cell_length_c   5.579
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   160.853
_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  0.667  0.333  0.250  1.0
  Ba  Ba1  1  0.333  0.667  0.750  1.0
  Mg  Mg2  1  0.667  0.333  0.750  1.0
  Ni  Ni3  1  0.000  0.000  0.495  1.0
  Ni  Ni4  1  0.000  0.000  0.005  1.0
  O  O5  1  0.849  0.698  0.750  1.0
  O  O6  1  0.152  0.848  0.250  1.0
  O  O7  1  0.697  0.848  0.250  1.0
  O  O8  1  0.302  0.151  0.750  1.0
  O  O9  1  0.152  0.303  0.250  1.0
  O  O10  1  0.849  0.151  0.750  1.0
[/CIF]
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