The material described by MgMn2O4 crystallizes in the monoclinic P2_1/c space group. Mg(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MnO5 trigonal bipyramids that share corners with four equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(1)O5 trigonal bipyramids, and  an edgeedge with one Mn(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 51-64°. In the second Mn site, Mn(2) is bonded to one O(2), two equivalent O(4), and three equivalent O(1) atoms to form distorted MnO6 octahedra that share corners with four equivalent Mn(1)O5 trigonal bipyramids and edges with four equivalent Mn(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1) and three equivalent Mn(2) atoms. In the second O site, O(2) is bonded to one Mg(1), one Mn(2), and two equivalent Mn(1) atoms to form distorted OMgMn3 trigonal pyramids that share corners with two equivalent O(3)Mg2Mn2 tetrahedra, corners with two equivalent O(2)MgMn3 trigonal pyramids, and edges with two equivalent O(3)Mg2Mn2 tetrahedra. In the third O site, O(3) is bonded to two equivalent Mg(1) and two equivalent Mn(1) atoms to form OMg2Mn2 tetrahedra that share corners with two equivalent O(3)Mg2Mn2 tetrahedra, corners with two equivalent O(2)MgMn3 trigonal pyramids,  an edgeedge with one O(3)Mg2Mn2 tetrahedra, and edges with two equivalent O(2)MgMn3 trigonal pyramids. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Mn(1), and two equivalent Mn(2) atoms. is represented by the CIF card [CIF]
data_MgMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.961
_cell_length_b   3.214
_cell_length_c   10.883
_cell_angle_alpha   82.302
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   310.538
_cell_formula_units_Z   4
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  0.785  0.044  0.344  1.0
  Mg  Mg1  1  0.215  0.956  0.656  1.0
  Mg  Mg2  1  0.285  0.956  0.156  1.0
  Mg  Mg3  1  0.715  0.044  0.844  1.0
  Mn  Mn4  1  0.583  0.514  0.117  1.0
  Mn  Mn5  1  0.917  0.514  0.617  1.0
  Mn  Mn6  1  0.083  0.486  0.383  1.0
  Mn  Mn7  1  0.417  0.486  0.883  1.0
  Mn  Mn8  1  0.446  0.830  0.389  1.0
  Mn  Mn9  1  0.554  0.170  0.611  1.0
  Mn  Mn10  1  0.946  0.170  0.111  1.0
  Mn  Mn11  1  0.054  0.830  0.889  1.0
  O  O12  1  0.095  0.776  0.067  1.0
  O  O13  1  0.905  0.224  0.933  1.0
  O  O14  1  0.595  0.224  0.433  1.0
  O  O15  1  0.405  0.776  0.567  1.0
  O  O16  1  0.976  0.940  0.722  1.0
  O  O17  1  0.024  0.060  0.278  1.0
  O  O18  1  0.476  0.060  0.778  1.0
  O  O19  1  0.524  0.940  0.222  1.0
  O  O20  1  0.376  0.513  0.058  1.0
  O  O21  1  0.624  0.487  0.942  1.0
  O  O22  1  0.876  0.487  0.442  1.0
  O  O23  1  0.124  0.513  0.558  1.0
  O  O24  1  0.215  0.503  0.821  1.0
  O  O25  1  0.785  0.497  0.179  1.0
  O  O26  1  0.285  0.503  0.321  1.0
  O  O27  1  0.715  0.497  0.679  1.0
[/CIF]
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The material described by MgMn2O4 crystallizes in the monoclinic P2_1/c space group. Mg(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MnO5 trigonal bipyramids that share corners with four equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(1)O5 trigonal bipyramids, and  an edgeedge with one Mn(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 51-64°. In the second Mn site, Mn(2) is bonded to one O(2), two equivalent O(4), and three equivalent O(1) atoms to form distorted MnO6 octahedra that share corners with four equivalent Mn(1)O5 trigonal bipyramids and edges with four equivalent Mn(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1) and three equivalent Mn(2) atoms. In the second O site, O(2) is bonded to one Mg(1), one Mn(2), and two equivalent Mn(1) atoms to form distorted OMgMn3 trigonal pyramids that share corners with two equivalent O(3)Mg2Mn2 tetrahedra, corners with two equivalent O(2)MgMn3 trigonal pyramids, and edges with two equivalent O(3)Mg2Mn2 tetrahedra. In the third O site, O(3) is bonded to two equivalent Mg(1) and two equivalent Mn(1) atoms to form OMg2Mn2 tetrahedra that share corners with two equivalent O(3)Mg2Mn2 tetrahedra, corners with two equivalent O(2)MgMn3 trigonal pyramids,  an edgeedge with one O(3)Mg2Mn2 tetrahedra, and edges with two equivalent O(2)MgMn3 trigonal pyramids. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Mn(1), and two equivalent Mn(2) atoms. is represented by the CIF card [CIF]
data_MgMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.961
_cell_length_b   3.214
_cell_length_c   10.883
_cell_angle_alpha   82.302
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   310.538
_cell_formula_units_Z   4
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  0.785  0.044  0.344  1.0
  Mg  Mg1  1  0.215  0.956  0.656  1.0
  Mg  Mg2  1  0.285  0.956  0.156  1.0
  Mg  Mg3  1  0.715  0.044  0.844  1.0
  Mn  Mn4  1  0.583  0.514  0.117  1.0
  Mn  Mn5  1  0.917  0.514  0.617  1.0
  Mn  Mn6  1  0.083  0.486  0.383  1.0
  Mn  Mn7  1  0.417  0.486  0.883  1.0
  Mn  Mn8  1  0.446  0.830  0.389  1.0
  Mn  Mn9  1  0.554  0.170  0.611  1.0
  Mn  Mn10  1  0.946  0.170  0.111  1.0
  Mn  Mn11  1  0.054  0.830  0.889  1.0
  O  O12  1  0.095  0.776  0.067  1.0
  O  O13  1  0.905  0.224  0.933  1.0
  O  O14  1  0.595  0.224  0.433  1.0
  O  O15  1  0.405  0.776  0.567  1.0
  O  O16  1  0.976  0.940  0.722  1.0
  O  O17  1  0.024  0.060  0.278  1.0
  O  O18  1  0.476  0.060  0.778  1.0
  O  O19  1  0.524  0.940  0.222  1.0
  O  O20  1  0.376  0.513  0.058  1.0
  O  O21  1  0.624  0.487  0.942  1.0
  O  O22  1  0.876  0.487  0.442  1.0
  O  O23  1  0.124  0.513  0.558  1.0
  O  O24  1  0.215  0.503  0.821  1.0
  O  O25  1  0.785  0.497  0.179  1.0
  O  O26  1  0.285  0.503  0.321  1.0
  O  O27  1  0.715  0.497  0.679  1.0
[/CIF]
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