The crystal structure described by Ba3MgMn3O9 is Krennerite-derived structured and crystallizes in the triclinic P1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), one O(9), and two equivalent O(5) atoms. In the second Ba site, Ba(2) is bonded in a 11-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), two equivalent O(7), two equivalent O(8), and two equivalent O(9) atoms. In the third Ba site, Ba(3) is bonded in a 8-coordinate geometry to one O(5), one O(7), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Mg(1) is bonded in a 5-coordinate geometry to one O(4), one O(6), one O(7), one O(8), and one O(9) atom. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. In the third Mn site, Mn(3) is bonded in an octahedral geometry to one O(4), one O(5), one O(6), one O(7), one O(8), and one O(9) atom. There are nine inequivalent O sites. In the first O site, O(1) is bonded to one Ba(1), one Ba(2), two equivalent Ba(3), one Mn(1), and one Mn(2) atom to form distorted OBa4Mn2 octahedra that share  a cornercorner with one O(7)Ba3MgMn2 octahedra, corners with two equivalent O(1)Ba4Mn2 octahedra, corners with three equivalent O(6)Ba2MgMn2 square pyramids, and edges with two equivalent O(7)Ba3MgMn2 octahedra. The corner-sharing octahedral tilt angles range from 6-12°. In the second O site, O(2) is bonded in a 6-coordinate 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 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Mn(1), and one Mn(2) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Mg(1), one Mn(2), and one Mn(3) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Ba(3), two equivalent Ba(1), one Mn(2), and one Mn(3) atom. In the sixth O site, O(6) is bonded to one Ba(1), one Ba(2), one Mg(1), one Mn(2), and one Mn(3) atom to form distorted OBa2MgMn2 square pyramids that share  a cornercorner with one O(7)Ba3MgMn2 octahedra, corners with three equivalent O(1)Ba4Mn2 octahedra, and  a faceface with one O(7)Ba3MgMn2 octahedra. The corner-sharing octahedral tilt angles range from 49-69°. In the seventh O site, O(7) is bonded to one Ba(3), two equivalent Ba(2), one Mg(1), one Mn(1), and one Mn(3) atom to form distorted OBa3MgMn2 octahedra that share  a cornercorner with one O(1)Ba4Mn2 octahedra, corners with two equivalent O(7)Ba3MgMn2 octahedra,  a cornercorner with one O(6)Ba2MgMn2 square pyramid, edges with two equivalent O(1)Ba4Mn2 octahedra, and  a faceface with one O(6)Ba2MgMn2 square pyramid. The corner-sharing octahedral tilt angles are 6°. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to two equivalent Ba(2), one Mg(1), one Mn(1), and one Mn(3) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Ba(1), two equivalent Ba(2), one Mg(1), one Mn(1), and one Mn(3) atom. is represented by the CIF file [CIF]
data_Ba3MgMn3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.303
_cell_length_b   9.422
_cell_length_c   8.232
_cell_angle_alpha   37.846
_cell_angle_beta   41.189
_cell_angle_gamma   38.331
_symmetry_Int_Tables_number   1
_cell_volume   229.588
_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  0.811  0.658  0.790  1.0
  Ba  Ba1  1  0.196  0.297  0.204  1.0
  Ba  Ba2  1  0.009  0.989  0.994  1.0
  Mg  Mg3  1  0.743  0.034  0.766  1.0
  Mn  Mn4  1  0.615  0.633  0.600  1.0
  Mn  Mn5  1  0.407  0.371  0.390  1.0
  Mn  Mn6  1  0.451  0.571  0.471  1.0
  O  O7  1  0.518  0.947  0.501  1.0
  O  O8  1  0.044  0.460  0.503  1.0
  O  O9  1  0.529  0.466  0.008  1.0
  O  O10  1  0.336  0.294  0.748  1.0
  O  O11  1  0.271  0.758  0.257  1.0
  O  O12  1  0.744  0.309  0.330  1.0
  O  O13  1  0.681  0.323  0.698  1.0
  O  O14  1  0.643  0.774  0.214  1.0
  O  O15  1  0.151  0.758  0.686  1.0
[/CIF]
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The crystal structure described by Ba3MgMn3O9 is Krennerite-derived structured and crystallizes in the triclinic P1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), one O(9), and two equivalent O(5) atoms. In the second Ba site, Ba(2) is bonded in a 11-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), two equivalent O(7), two equivalent O(8), and two equivalent O(9) atoms. In the third Ba site, Ba(3) is bonded in a 8-coordinate geometry to one O(5), one O(7), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Mg(1) is bonded in a 5-coordinate geometry to one O(4), one O(6), one O(7), one O(8), and one O(9) atom. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. In the third Mn site, Mn(3) is bonded in an octahedral geometry to one O(4), one O(5), one O(6), one O(7), one O(8), and one O(9) atom. There are nine inequivalent O sites. In the first O site, O(1) is bonded to one Ba(1), one Ba(2), two equivalent Ba(3), one Mn(1), and one Mn(2) atom to form distorted OBa4Mn2 octahedra that share  a cornercorner with one O(7)Ba3MgMn2 octahedra, corners with two equivalent O(1)Ba4Mn2 octahedra, corners with three equivalent O(6)Ba2MgMn2 square pyramids, and edges with two equivalent O(7)Ba3MgMn2 octahedra. The corner-sharing octahedral tilt angles range from 6-12°. In the second O site, O(2) is bonded in a 6-coordinate 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 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Mn(1), and one Mn(2) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Mg(1), one Mn(2), and one Mn(3) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Ba(3), two equivalent Ba(1), one Mn(2), and one Mn(3) atom. In the sixth O site, O(6) is bonded to one Ba(1), one Ba(2), one Mg(1), one Mn(2), and one Mn(3) atom to form distorted OBa2MgMn2 square pyramids that share  a cornercorner with one O(7)Ba3MgMn2 octahedra, corners with three equivalent O(1)Ba4Mn2 octahedra, and  a faceface with one O(7)Ba3MgMn2 octahedra. The corner-sharing octahedral tilt angles range from 49-69°. In the seventh O site, O(7) is bonded to one Ba(3), two equivalent Ba(2), one Mg(1), one Mn(1), and one Mn(3) atom to form distorted OBa3MgMn2 octahedra that share  a cornercorner with one O(1)Ba4Mn2 octahedra, corners with two equivalent O(7)Ba3MgMn2 octahedra,  a cornercorner with one O(6)Ba2MgMn2 square pyramid, edges with two equivalent O(1)Ba4Mn2 octahedra, and  a faceface with one O(6)Ba2MgMn2 square pyramid. The corner-sharing octahedral tilt angles are 6°. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to two equivalent Ba(2), one Mg(1), one Mn(1), and one Mn(3) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Ba(1), two equivalent Ba(2), one Mg(1), one Mn(1), and one Mn(3) atom. is represented by the CIF file [CIF]
data_Ba3MgMn3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.303
_cell_length_b   9.422
_cell_length_c   8.232
_cell_angle_alpha   37.846
_cell_angle_beta   41.189
_cell_angle_gamma   38.331
_symmetry_Int_Tables_number   1
_cell_volume   229.588
_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  0.811  0.658  0.790  1.0
  Ba  Ba1  1  0.196  0.297  0.204  1.0
  Ba  Ba2  1  0.009  0.989  0.994  1.0
  Mg  Mg3  1  0.743  0.034  0.766  1.0
  Mn  Mn4  1  0.615  0.633  0.600  1.0
  Mn  Mn5  1  0.407  0.371  0.390  1.0
  Mn  Mn6  1  0.451  0.571  0.471  1.0
  O  O7  1  0.518  0.947  0.501  1.0
  O  O8  1  0.044  0.460  0.503  1.0
  O  O9  1  0.529  0.466  0.008  1.0
  O  O10  1  0.336  0.294  0.748  1.0
  O  O11  1  0.271  0.758  0.257  1.0
  O  O12  1  0.744  0.309  0.330  1.0
  O  O13  1  0.681  0.323  0.698  1.0
  O  O14  1  0.643  0.774  0.214  1.0
  O  O15  1  0.151  0.758  0.686  1.0
[/CIF]
.