The compound described by MgMn2O4 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form MgO6 octahedra that share corners with three equivalent Mn(2)O6 octahedra, corners with three equivalent Mn(3)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-15°. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with four equivalent Mg(1)O6 octahedra. In the second Mn site, Mn(2) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form MnO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-15°. In the third Mn site, Mn(3) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form MnO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-15°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a see-saw-like geometry to one Mg(1), one Mn(2), and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded in a see-saw-like geometry to one Mg(1), one Mn(3), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded to two equivalent Mg(1), one Mn(1), one Mn(2), and one Mn(3) atom to form a mixture of corner and edge-sharing OMg2Mn3 square pyramids. is represented by the CIF card [CIF]
data_MgMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.978
_cell_length_b   5.214
_cell_length_c   5.432
_cell_angle_alpha   108.427
_cell_angle_beta   89.922
_cell_angle_gamma   89.986
_symmetry_Int_Tables_number   1
_cell_volume   80.029
_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  0.500  0.500  1.000  1.0
  Mn  Mn1  1  0.000  0.000  1.000  1.0
  Mn  Mn2  1  0.500  0.000  0.500  1.0
  O  O3  1  0.499  0.210  0.199  1.0
  O  O4  1  0.501  0.790  0.801  1.0
  O  O5  1  0.000  0.235  0.787  1.0
  O  O6  1  1.000  0.764  0.213  1.0
[/CIF]
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The compound described by MgMn2O4 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form MgO6 octahedra that share corners with three equivalent Mn(2)O6 octahedra, corners with three equivalent Mn(3)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-15°. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with four equivalent Mg(1)O6 octahedra. In the second Mn site, Mn(2) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form MnO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-15°. In the third Mn site, Mn(3) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form MnO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-15°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a see-saw-like geometry to one Mg(1), one Mn(2), and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded in a see-saw-like geometry to one Mg(1), one Mn(3), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded to two equivalent Mg(1), one Mn(1), one Mn(2), and one Mn(3) atom to form a mixture of corner and edge-sharing OMg2Mn3 square pyramids. is represented by the CIF card [CIF]
data_MgMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.978
_cell_length_b   5.214
_cell_length_c   5.432
_cell_angle_alpha   108.427
_cell_angle_beta   89.922
_cell_angle_gamma   89.986
_symmetry_Int_Tables_number   1
_cell_volume   80.029
_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  0.500  0.500  1.000  1.0
  Mn  Mn1  1  0.000  0.000  1.000  1.0
  Mn  Mn2  1  0.500  0.000  0.500  1.0
  O  O3  1  0.499  0.210  0.199  1.0
  O  O4  1  0.501  0.790  0.801  1.0
  O  O5  1  0.000  0.235  0.787  1.0
  O  O6  1  1.000  0.764  0.213  1.0
[/CIF]
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