The crystal structure described by MgMn6O12 crystallizes in the monoclinic P2 space group. Mg(1) is bonded to two equivalent O(1) and four equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent Mn(4)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, edges with four equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(4)O5 trigonal bipyramids. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form edge-sharing MnO6 octahedra. 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 corners with two equivalent Mn(4)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. In the third Mn site, Mn(3) is bonded to two equivalent O(6) and four equivalent O(5) atoms to form MnO6 octahedra that share edges with two equivalent Mn(3)O6 octahedra and edges with four equivalent Mn(4)O5 trigonal bipyramids. In the fourth Mn site, Mn(4) is bonded to one O(5), two equivalent O(4), and two equivalent O(6) atoms to form distorted MnO5 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(4)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 33-59°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1) and two equivalent Mn(2) atoms. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Mn(2) and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mn(1) and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded to two equivalent Mg(1), one Mn(2), and two equivalent Mn(4) atoms to form a mixture of distorted edge and corner-sharing OMg2Mn3 trigonal bipyramids. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Mn(4) and two equivalent Mn(3) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Mn(3) and two equivalent Mn(4) atoms. is represented by the CIF file [CIF]
data_MgMn6O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.917
_cell_length_b   10.752
_cell_length_c   10.282
_cell_angle_alpha   104.203
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   312.655
_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
  Mg  Mg0  1  0.510  0.000  0.000  1.0
  Mn  Mn1  1  0.511  0.000  0.500  1.0
  Mn  Mn2  1  0.010  0.991  0.252  1.0
  Mn  Mn3  1  0.010  0.009  0.748  1.0
  Mn  Mn4  1  1.000  0.500  0.000  1.0
  Mn  Mn5  1  0.504  0.262  0.006  1.0
  Mn  Mn6  1  0.504  0.738  0.994  1.0
  O  O7  1  0.510  0.920  0.805  1.0
  O  O8  1  0.510  0.080  0.195  1.0
  O  O9  1  0.011  0.911  0.563  1.0
  O  O10  1  0.011  0.089  0.437  1.0
  O  O11  1  0.510  0.900  0.315  1.0
  O  O12  1  0.510  0.100  0.685  1.0
  O  O13  1  0.008  0.876  0.057  1.0
  O  O14  1  0.008  0.124  0.943  1.0
  O  O15  1  0.500  0.596  0.100  1.0
  O  O16  1  0.500  0.404  0.900  1.0
  O  O17  1  0.999  0.363  0.096  1.0
  O  O18  1  0.999  0.637  0.904  1.0
[/CIF]
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The crystal structure described by MgMn6O12 crystallizes in the monoclinic P2 space group. Mg(1) is bonded to two equivalent O(1) and four equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent Mn(4)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, edges with four equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(4)O5 trigonal bipyramids. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form edge-sharing MnO6 octahedra. 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 corners with two equivalent Mn(4)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. In the third Mn site, Mn(3) is bonded to two equivalent O(6) and four equivalent O(5) atoms to form MnO6 octahedra that share edges with two equivalent Mn(3)O6 octahedra and edges with four equivalent Mn(4)O5 trigonal bipyramids. In the fourth Mn site, Mn(4) is bonded to one O(5), two equivalent O(4), and two equivalent O(6) atoms to form distorted MnO5 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(4)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 33-59°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1) and two equivalent Mn(2) atoms. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Mn(2) and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mn(1) and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded to two equivalent Mg(1), one Mn(2), and two equivalent Mn(4) atoms to form a mixture of distorted edge and corner-sharing OMg2Mn3 trigonal bipyramids. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Mn(4) and two equivalent Mn(3) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Mn(3) and two equivalent Mn(4) atoms. is represented by the CIF file [CIF]
data_MgMn6O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.917
_cell_length_b   10.752
_cell_length_c   10.282
_cell_angle_alpha   104.203
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   312.655
_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
  Mg  Mg0  1  0.510  0.000  0.000  1.0
  Mn  Mn1  1  0.511  0.000  0.500  1.0
  Mn  Mn2  1  0.010  0.991  0.252  1.0
  Mn  Mn3  1  0.010  0.009  0.748  1.0
  Mn  Mn4  1  1.000  0.500  0.000  1.0
  Mn  Mn5  1  0.504  0.262  0.006  1.0
  Mn  Mn6  1  0.504  0.738  0.994  1.0
  O  O7  1  0.510  0.920  0.805  1.0
  O  O8  1  0.510  0.080  0.195  1.0
  O  O9  1  0.011  0.911  0.563  1.0
  O  O10  1  0.011  0.089  0.437  1.0
  O  O11  1  0.510  0.900  0.315  1.0
  O  O12  1  0.510  0.100  0.685  1.0
  O  O13  1  0.008  0.876  0.057  1.0
  O  O14  1  0.008  0.124  0.943  1.0
  O  O15  1  0.500  0.596  0.100  1.0
  O  O16  1  0.500  0.404  0.900  1.0
  O  O17  1  0.999  0.363  0.096  1.0
  O  O18  1  0.999  0.637  0.904  1.0
[/CIF]
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