The compound described by Ba3MgMn3O9 is Krennerite-derived structured and crystallizes in the monoclinic Cm space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 11-coordinate geometry to one O(6), two equivalent O(1), two equivalent O(4), two equivalent O(5), and four equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 3-coordinate geometry to one O(2), one O(4), and two equivalent O(3) atoms. In the third Ba site, Ba(3) is bonded in a 9-coordinate geometry to one O(6), two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. Mg(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(5) atoms to form distorted MgO5 trigonal bipyramids that share corners with two equivalent Mn(3)O6 octahedra and  a faceface with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles are 38°. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(5) atoms. In the second Mn site, Mn(2) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form MnO6 octahedra that share  a faceface with one Mn(3)O6 octahedra and  a faceface with one Mg(1)O5 trigonal bipyramid. In the third Mn site, Mn(3) is bonded to one O(4), one O(6), two equivalent O(3), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Mg(1)O5 trigonal bipyramids 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 3-coordinate geometry to one Ba(1), two equivalent Ba(3), one Mg(1), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Ba(2), two equivalent Ba(3), one Mg(1), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Ba(2), one Ba(3), two equivalent Ba(1), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ba(2), two equivalent Ba(1), one Mn(2), and one Mn(3) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Ba(1), one Mg(1), one Mn(1), and one Mn(3) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(3), and one Mn(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3MgMn3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.941
_cell_length_b   8.087
_cell_length_c   8.087
_cell_angle_alpha   41.543
_cell_angle_beta   40.645
_cell_angle_gamma   40.645
_symmetry_Int_Tables_number   1
_cell_volume   226.591
_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  0.760  0.798  0.798  1.0
  Ba  Ba1  1  0.091  0.237  0.237  1.0
  Ba  Ba2  1  0.129  0.949  0.949  1.0
  Mg  Mg3  1  0.533  0.149  0.149  1.0
  Mn  Mn4  1  0.736  0.572  0.572  1.0
  Mn  Mn5  1  0.442  0.363  0.363  1.0
  Mn  Mn6  1  0.421  0.549  0.549  1.0
  O  O7  1  0.624  0.971  0.438  1.0
  O  O8  1  0.165  0.390  0.390  1.0
  O  O9  1  0.624  0.438  0.971  1.0
  O  O10  1  0.282  0.297  0.744  1.0
  O  O11  1  0.282  0.744  0.297  1.0
  O  O12  1  0.708  0.320  0.320  1.0
  O  O13  1  0.595  0.298  0.768  1.0
  O  O14  1  0.595  0.768  0.298  1.0
  O  O15  1  0.126  0.757  0.757  1.0
[/CIF]
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The compound described by Ba3MgMn3O9 is Krennerite-derived structured and crystallizes in the monoclinic Cm space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 11-coordinate geometry to one O(6), two equivalent O(1), two equivalent O(4), two equivalent O(5), and four equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 3-coordinate geometry to one O(2), one O(4), and two equivalent O(3) atoms. In the third Ba site, Ba(3) is bonded in a 9-coordinate geometry to one O(6), two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. Mg(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(5) atoms to form distorted MgO5 trigonal bipyramids that share corners with two equivalent Mn(3)O6 octahedra and  a faceface with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles are 38°. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(5) atoms. In the second Mn site, Mn(2) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form MnO6 octahedra that share  a faceface with one Mn(3)O6 octahedra and  a faceface with one Mg(1)O5 trigonal bipyramid. In the third Mn site, Mn(3) is bonded to one O(4), one O(6), two equivalent O(3), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Mg(1)O5 trigonal bipyramids 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 3-coordinate geometry to one Ba(1), two equivalent Ba(3), one Mg(1), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Ba(2), two equivalent Ba(3), one Mg(1), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Ba(2), one Ba(3), two equivalent Ba(1), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ba(2), two equivalent Ba(1), one Mn(2), and one Mn(3) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Ba(1), one Mg(1), one Mn(1), and one Mn(3) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(3), and one Mn(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3MgMn3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.941
_cell_length_b   8.087
_cell_length_c   8.087
_cell_angle_alpha   41.543
_cell_angle_beta   40.645
_cell_angle_gamma   40.645
_symmetry_Int_Tables_number   1
_cell_volume   226.591
_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  0.760  0.798  0.798  1.0
  Ba  Ba1  1  0.091  0.237  0.237  1.0
  Ba  Ba2  1  0.129  0.949  0.949  1.0
  Mg  Mg3  1  0.533  0.149  0.149  1.0
  Mn  Mn4  1  0.736  0.572  0.572  1.0
  Mn  Mn5  1  0.442  0.363  0.363  1.0
  Mn  Mn6  1  0.421  0.549  0.549  1.0
  O  O7  1  0.624  0.971  0.438  1.0
  O  O8  1  0.165  0.390  0.390  1.0
  O  O9  1  0.624  0.438  0.971  1.0
  O  O10  1  0.282  0.297  0.744  1.0
  O  O11  1  0.282  0.744  0.297  1.0
  O  O12  1  0.708  0.320  0.320  1.0
  O  O13  1  0.595  0.298  0.768  1.0
  O  O14  1  0.595  0.768  0.298  1.0
  O  O15  1  0.126  0.757  0.757  1.0
[/CIF]
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