The material described by Ba3MgNb2MnO9 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 9-coordinate geometry to one Mg(1), one O(4), two equivalent O(1), two equivalent O(3), and three equivalent O(2) atoms. In the second Ba site, Ba(2) is bonded to two equivalent O(2), two equivalent O(4), four equivalent O(1), and four equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(2)O12 cuboctahedra, faces with two equivalent Mn(1)O6 octahedra, and faces with six equivalent Nb(1)O6 octahedra. Mg(1) is bonded in a square co-planar geometry to two equivalent Ba(1) and four equivalent O(1) atoms. 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, corners with three equivalent Mn(1)O6 octahedra, and faces with three equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-9°. Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MnO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra and faces with two equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 5-9°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), one Mg(1), one Nb(1), and one Mn(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Ba(2), three equivalent Ba(1), one Nb(1), and one Mn(1) atom. In the third O site, O(3) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms to form a mixture of distorted corner and face-sharing OBa4Nb2 octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the fourth O site, O(4) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_Ba3MgMnNb2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.190
_cell_length_b   6.190
_cell_length_c   7.464
_cell_angle_alpha   86.157
_cell_angle_beta   93.843
_cell_angle_gamma   123.000
_symmetry_Int_Tables_number   1
_cell_volume   239.120
_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  0.279  0.721  0.697  1.0
  Ba  Ba1  1  0.721  0.279  0.303  1.0
  Ba  Ba2  1  1.000  1.000  1.000  1.0
  Mg  Mg3  1  0.500  0.500  0.500  1.0
  Mn  Mn4  1  0.000  1.000  0.500  1.0
  Nb  Nb5  1  0.338  0.662  0.157  1.0
  Nb  Nb6  1  0.662  0.338  0.843  1.0
  O  O7  1  0.332  0.195  0.671  1.0
  O  O8  1  0.802  0.198  0.683  1.0
  O  O9  1  0.805  0.668  0.671  1.0
  O  O10  1  0.198  0.802  0.317  1.0
  O  O11  1  0.668  0.805  0.329  1.0
  O  O12  1  0.195  0.332  0.329  1.0
  O  O13  1  0.500  0.000  0.000  1.0
  O  O14  1  1.000  0.500  0.000  1.0
  O  O15  1  0.500  0.500  0.000  1.0
[/CIF]
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The material described by Ba3MgNb2MnO9 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 9-coordinate geometry to one Mg(1), one O(4), two equivalent O(1), two equivalent O(3), and three equivalent O(2) atoms. In the second Ba site, Ba(2) is bonded to two equivalent O(2), two equivalent O(4), four equivalent O(1), and four equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(2)O12 cuboctahedra, faces with two equivalent Mn(1)O6 octahedra, and faces with six equivalent Nb(1)O6 octahedra. Mg(1) is bonded in a square co-planar geometry to two equivalent Ba(1) and four equivalent O(1) atoms. 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, corners with three equivalent Mn(1)O6 octahedra, and faces with three equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-9°. Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MnO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra and faces with two equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 5-9°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), one Mg(1), one Nb(1), and one Mn(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Ba(2), three equivalent Ba(1), one Nb(1), and one Mn(1) atom. In the third O site, O(3) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms to form a mixture of distorted corner and face-sharing OBa4Nb2 octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the fourth O site, O(4) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_Ba3MgMnNb2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.190
_cell_length_b   6.190
_cell_length_c   7.464
_cell_angle_alpha   86.157
_cell_angle_beta   93.843
_cell_angle_gamma   123.000
_symmetry_Int_Tables_number   1
_cell_volume   239.120
_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  0.279  0.721  0.697  1.0
  Ba  Ba1  1  0.721  0.279  0.303  1.0
  Ba  Ba2  1  1.000  1.000  1.000  1.0
  Mg  Mg3  1  0.500  0.500  0.500  1.0
  Mn  Mn4  1  0.000  1.000  0.500  1.0
  Nb  Nb5  1  0.338  0.662  0.157  1.0
  Nb  Nb6  1  0.662  0.338  0.843  1.0
  O  O7  1  0.332  0.195  0.671  1.0
  O  O8  1  0.802  0.198  0.683  1.0
  O  O9  1  0.805  0.668  0.671  1.0
  O  O10  1  0.198  0.802  0.317  1.0
  O  O11  1  0.668  0.805  0.329  1.0
  O  O12  1  0.195  0.332  0.329  1.0
  O  O13  1  0.500  0.000  0.000  1.0
  O  O14  1  1.000  0.500  0.000  1.0
  O  O15  1  0.500  0.500  0.000  1.0
[/CIF]
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