The structure described by Ba3MgMn3O9 crystallizes in the monoclinic Cm space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one O(2), one O(6), two equivalent O(1), two equivalent O(3), two equivalent O(5), and four equivalent O(4) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Mn(1)O6 octahedra,  a faceface with one Mn(1)O6 octahedra, faces with three equivalent Mn(2)O6 octahedra, and faces with three equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 10°. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(2), two equivalent O(1), two equivalent O(6), and four equivalent O(5) atoms. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to one Mg(1), one O(6), two equivalent O(2), two equivalent O(5), and four equivalent O(1) atoms. Mg(1) is bonded in a trigonal planar geometry to one Ba(3), one O(3), and two equivalent O(4) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Mn(2)O6 octahedra,  a faceface with one Ba(1)O12 cuboctahedra, and  a faceface with one Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second Mn site, Mn(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with three equivalent Mn(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, and  a faceface with one Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the third Mn site, Mn(3) is bonded to one O(3), one O(6), two equivalent O(4), and two equivalent O(5) atoms to form MnO6 octahedra that share faces with three equivalent Ba(1)O12 cuboctahedra,  a faceface with one Mn(1)O6 octahedra, and  a faceface with one Mn(2)O6 octahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Ba(1), one Mg(1), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Ba(1), one Mg(1), one Mn(2), and one Mn(3) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(2), one Mn(1), and one Mn(3) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(2), one Mn(1), and one Mn(3) atom. is represented by the CIF card [CIF]
data_Ba3MgMn3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.395
_cell_length_b   8.395
_cell_length_c   8.394
_cell_angle_alpha   40.858
_cell_angle_beta   40.858
_cell_angle_gamma   40.852
_symmetry_Int_Tables_number   1
_cell_volume   228.467
_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  0.778  0.778  0.776  1.0
  Ba  Ba1  1  0.238  0.238  0.238  1.0
  Ba  Ba2  1  0.969  0.969  0.969  1.0
  Mg  Mg3  1  0.107  0.107  0.106  1.0
  Mn  Mn4  1  0.620  0.620  0.620  1.0
  Mn  Mn5  1  0.381  0.381  0.381  1.0
  Mn  Mn6  1  0.505  0.505  0.504  1.0
  O  O7  1  0.503  0.988  0.503  1.0
  O  O8  1  0.988  0.503  0.503  1.0
  O  O9  1  0.503  0.503  0.988  1.0
  O  O10  1  0.300  0.300  0.753  1.0
  O  O11  1  0.300  0.754  0.298  1.0
  O  O12  1  0.754  0.300  0.298  1.0
  O  O13  1  0.704  0.264  0.703  1.0
  O  O14  1  0.704  0.704  0.264  1.0
  O  O15  1  0.264  0.704  0.703  1.0
[/CIF]
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The structure described by Ba3MgMn3O9 crystallizes in the monoclinic Cm space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one O(2), one O(6), two equivalent O(1), two equivalent O(3), two equivalent O(5), and four equivalent O(4) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Mn(1)O6 octahedra,  a faceface with one Mn(1)O6 octahedra, faces with three equivalent Mn(2)O6 octahedra, and faces with three equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 10°. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(2), two equivalent O(1), two equivalent O(6), and four equivalent O(5) atoms. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to one Mg(1), one O(6), two equivalent O(2), two equivalent O(5), and four equivalent O(1) atoms. Mg(1) is bonded in a trigonal planar geometry to one Ba(3), one O(3), and two equivalent O(4) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Mn(2)O6 octahedra,  a faceface with one Ba(1)O12 cuboctahedra, and  a faceface with one Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second Mn site, Mn(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with three equivalent Mn(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, and  a faceface with one Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the third Mn site, Mn(3) is bonded to one O(3), one O(6), two equivalent O(4), and two equivalent O(5) atoms to form MnO6 octahedra that share faces with three equivalent Ba(1)O12 cuboctahedra,  a faceface with one Mn(1)O6 octahedra, and  a faceface with one Mn(2)O6 octahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Ba(1), one Mg(1), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Ba(1), one Mg(1), one Mn(2), and one Mn(3) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(2), one Mn(1), and one Mn(3) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(2), one Mn(1), and one Mn(3) atom. is represented by the CIF card [CIF]
data_Ba3MgMn3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.395
_cell_length_b   8.395
_cell_length_c   8.394
_cell_angle_alpha   40.858
_cell_angle_beta   40.858
_cell_angle_gamma   40.852
_symmetry_Int_Tables_number   1
_cell_volume   228.467
_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  0.778  0.778  0.776  1.0
  Ba  Ba1  1  0.238  0.238  0.238  1.0
  Ba  Ba2  1  0.969  0.969  0.969  1.0
  Mg  Mg3  1  0.107  0.107  0.106  1.0
  Mn  Mn4  1  0.620  0.620  0.620  1.0
  Mn  Mn5  1  0.381  0.381  0.381  1.0
  Mn  Mn6  1  0.505  0.505  0.504  1.0
  O  O7  1  0.503  0.988  0.503  1.0
  O  O8  1  0.988  0.503  0.503  1.0
  O  O9  1  0.503  0.503  0.988  1.0
  O  O10  1  0.300  0.300  0.753  1.0
  O  O11  1  0.300  0.754  0.298  1.0
  O  O12  1  0.754  0.300  0.298  1.0
  O  O13  1  0.704  0.264  0.703  1.0
  O  O14  1  0.704  0.704  0.264  1.0
  O  O15  1  0.264  0.704  0.703  1.0
[/CIF]
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