The material structure described by Ba3MgNb2CoO9 is Orthorhombic Perovskite-derived structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 11-coordinate geometry to one Co(1), one O(4), two equivalent O(1), three equivalent O(2), and four equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to two equivalent O(4), four equivalent O(1), and four equivalent O(3) atoms. Mg(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form distorted MgO6 octahedra that share faces with two equivalent Nb(1)O6 octahedra. Nb(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with three equivalent Nb(1)O6 octahedra and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedra are not tilted. Co(1) is bonded in a distorted square co-planar geometry to two equivalent Ba(1) and four equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded in a 5-coordinate geometry to three equivalent Ba(1), one Mg(1), and one Nb(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(2), two equivalent Ba(1), one Mg(1), one Nb(1), and one Co(1) atom. In the fourth O site, O(4) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms to form distorted corner-sharing OBa4Nb2 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3MgNb2CoO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.750
_cell_length_b   6.151
_cell_length_c   7.941
_cell_angle_alpha   104.780
_cell_angle_beta   90.028
_cell_angle_gamma   117.852
_symmetry_Int_Tables_number   1
_cell_volume   237.735
_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  0.725  0.449  0.307  1.0
  Ba  Ba1  1  0.000  0.000  0.000  1.0
  Ba  Ba2  1  0.275  0.551  0.693  1.0
  Mg  Mg3  1  0.500  0.000  0.500  1.0
  Nb  Nb4  1  0.370  0.739  0.155  1.0
  Nb  Nb5  1  0.630  0.261  0.845  1.0
  Co  Co6  1  0.000  0.000  0.500  1.0
  O  O7  1  0.500  0.500  0.000  1.0
  O  O8  1  0.288  0.575  0.349  1.0
  O  O9  1  0.712  0.425  0.651  1.0
  O  O10  1  0.000  0.500  0.000  1.0
  O  O11  1  0.245  0.980  0.306  1.0
  O  O12  1  0.265  0.020  0.694  1.0
  O  O13  1  0.755  0.020  0.694  1.0
  O  O14  1  0.735  0.980  0.306  1.0
  O  O15  1  0.500  0.000  0.000  1.0
[/CIF]
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The material structure described by Ba3MgNb2CoO9 is Orthorhombic Perovskite-derived structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 11-coordinate geometry to one Co(1), one O(4), two equivalent O(1), three equivalent O(2), and four equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to two equivalent O(4), four equivalent O(1), and four equivalent O(3) atoms. Mg(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form distorted MgO6 octahedra that share faces with two equivalent Nb(1)O6 octahedra. Nb(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with three equivalent Nb(1)O6 octahedra and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedra are not tilted. Co(1) is bonded in a distorted square co-planar geometry to two equivalent Ba(1) and four equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded in a 5-coordinate geometry to three equivalent Ba(1), one Mg(1), and one Nb(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(2), two equivalent Ba(1), one Mg(1), one Nb(1), and one Co(1) atom. In the fourth O site, O(4) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms to form distorted corner-sharing OBa4Nb2 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3MgNb2CoO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.750
_cell_length_b   6.151
_cell_length_c   7.941
_cell_angle_alpha   104.780
_cell_angle_beta   90.028
_cell_angle_gamma   117.852
_symmetry_Int_Tables_number   1
_cell_volume   237.735
_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  0.725  0.449  0.307  1.0
  Ba  Ba1  1  0.000  0.000  0.000  1.0
  Ba  Ba2  1  0.275  0.551  0.693  1.0
  Mg  Mg3  1  0.500  0.000  0.500  1.0
  Nb  Nb4  1  0.370  0.739  0.155  1.0
  Nb  Nb5  1  0.630  0.261  0.845  1.0
  Co  Co6  1  0.000  0.000  0.500  1.0
  O  O7  1  0.500  0.500  0.000  1.0
  O  O8  1  0.288  0.575  0.349  1.0
  O  O9  1  0.712  0.425  0.651  1.0
  O  O10  1  0.000  0.500  0.000  1.0
  O  O11  1  0.245  0.980  0.306  1.0
  O  O12  1  0.265  0.020  0.694  1.0
  O  O13  1  0.755  0.020  0.694  1.0
  O  O14  1  0.735  0.980  0.306  1.0
  O  O15  1  0.500  0.000  0.000  1.0
[/CIF]
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