The structure described by MgMn2O4 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(4) atoms to form MgO5 square pyramids that share corners with four equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(1)O5 square pyramids,  an edgeedge with one Mn(1)O5 square pyramid, edges with two equivalent Mg(1)O5 square pyramids, and  a faceface with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 36-62°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form MnO5 square pyramids that share corners with four equivalent Mn(2)O6 octahedra, corners with four equivalent Mg(1)O5 square pyramids,  an edgeedge with one Mg(1)O5 square pyramid, and edges with two equivalent Mn(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 50-51°. In the second Mn site, Mn(2) is bonded to one O(1), two equivalent O(2), and three equivalent O(4) atoms to form distorted MnO6 octahedra that share corners with four equivalent Mg(1)O5 square pyramids, corners with four equivalent Mn(1)O5 square pyramids, edges with four equivalent Mn(2)O6 octahedra, and  a faceface with one Mg(1)O5 square pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Mn(2), and two equivalent Mn(1) atoms to form distorted OMgMn3 tetrahedra that share corners with two equivalent O(1)MgMn3 tetrahedra,  a cornercorner with one O(4)Mg2Mn3 trigonal bipyramid, and edges with two equivalent O(4)Mg2Mn3 trigonal bipyramids. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Mn(1) and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Mn(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Mg(1) and three equivalent Mn(2) atoms to form distorted OMg2Mn3 trigonal bipyramids that share  a cornercorner with one O(1)MgMn3 tetrahedra, edges with two equivalent O(1)MgMn3 tetrahedra, and edges with four equivalent O(4)Mg2Mn3 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.911
_cell_length_b   7.911
_cell_length_c   9.589
_cell_angle_alpha   53.840
_cell_angle_beta   53.840
_cell_angle_gamma   20.910
_symmetry_Int_Tables_number   1
_cell_volume   171.340
_cell_formula_units_Z   2
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  0.693  0.693  0.829  1.0
  Mg  Mg1  1  0.307  0.307  0.171  1.0
  Mn  Mn2  1  0.388  0.388  0.815  1.0
  Mn  Mn3  1  0.850  0.850  0.482  1.0
  Mn  Mn4  1  0.150  0.150  0.518  1.0
  Mn  Mn5  1  0.612  0.612  0.185  1.0
  O  O6  1  0.143  0.143  0.282  1.0
  O  O7  1  0.555  0.555  0.654  1.0
  O  O8  1  0.445  0.445  0.346  1.0
  O  O9  1  0.857  0.857  0.718  1.0
  O  O10  1  0.865  0.865  0.983  1.0
  O  O11  1  0.237  0.237  0.640  1.0
  O  O12  1  0.135  0.135  0.017  1.0
  O  O13  1  0.763  0.763  0.360  1.0
[/CIF]
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The structure described by MgMn2O4 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(4) atoms to form MgO5 square pyramids that share corners with four equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(1)O5 square pyramids,  an edgeedge with one Mn(1)O5 square pyramid, edges with two equivalent Mg(1)O5 square pyramids, and  a faceface with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 36-62°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form MnO5 square pyramids that share corners with four equivalent Mn(2)O6 octahedra, corners with four equivalent Mg(1)O5 square pyramids,  an edgeedge with one Mg(1)O5 square pyramid, and edges with two equivalent Mn(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 50-51°. In the second Mn site, Mn(2) is bonded to one O(1), two equivalent O(2), and three equivalent O(4) atoms to form distorted MnO6 octahedra that share corners with four equivalent Mg(1)O5 square pyramids, corners with four equivalent Mn(1)O5 square pyramids, edges with four equivalent Mn(2)O6 octahedra, and  a faceface with one Mg(1)O5 square pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Mn(2), and two equivalent Mn(1) atoms to form distorted OMgMn3 tetrahedra that share corners with two equivalent O(1)MgMn3 tetrahedra,  a cornercorner with one O(4)Mg2Mn3 trigonal bipyramid, and edges with two equivalent O(4)Mg2Mn3 trigonal bipyramids. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Mn(1) and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Mn(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Mg(1) and three equivalent Mn(2) atoms to form distorted OMg2Mn3 trigonal bipyramids that share  a cornercorner with one O(1)MgMn3 tetrahedra, edges with two equivalent O(1)MgMn3 tetrahedra, and edges with four equivalent O(4)Mg2Mn3 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.911
_cell_length_b   7.911
_cell_length_c   9.589
_cell_angle_alpha   53.840
_cell_angle_beta   53.840
_cell_angle_gamma   20.910
_symmetry_Int_Tables_number   1
_cell_volume   171.340
_cell_formula_units_Z   2
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  0.693  0.693  0.829  1.0
  Mg  Mg1  1  0.307  0.307  0.171  1.0
  Mn  Mn2  1  0.388  0.388  0.815  1.0
  Mn  Mn3  1  0.850  0.850  0.482  1.0
  Mn  Mn4  1  0.150  0.150  0.518  1.0
  Mn  Mn5  1  0.612  0.612  0.185  1.0
  O  O6  1  0.143  0.143  0.282  1.0
  O  O7  1  0.555  0.555  0.654  1.0
  O  O8  1  0.445  0.445  0.346  1.0
  O  O9  1  0.857  0.857  0.718  1.0
  O  O10  1  0.865  0.865  0.983  1.0
  O  O11  1  0.237  0.237  0.640  1.0
  O  O12  1  0.135  0.135  0.017  1.0
  O  O13  1  0.763  0.763  0.360  1.0
[/CIF]
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