The compound described by MgMn4O8 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with four equivalent Mn(1)O5 trigonal bipyramids, edges with four equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(1)O5 trigonal bipyramids. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3) and four equivalent O(1) atoms to form distorted MnO5 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with six equivalent Mn(2)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Mn(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 49-58°. In the second Mn site, Mn(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. There are three 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 a mixture of corner and edge-sharing OMgMn3 trigonal pyramids. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1) and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mn(1) and two equivalent Mn(2) atoms. is represented by the CIF file [CIF]
data_MgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.740
_cell_length_b   5.836
_cell_length_c   5.732
_cell_angle_alpha   60.586
_cell_angle_beta   60.049
_cell_angle_gamma   84.447
_symmetry_Int_Tables_number   1
_cell_volume   142.092
_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  0.625  0.125  0.116  1.0
  Mn  Mn1  1  0.190  0.059  0.867  1.0
  Mn  Mn2  1  0.060  0.191  0.365  1.0
  Mn  Mn3  1  0.625  0.625  0.116  1.0
  Mn  Mn4  1  0.625  0.625  0.616  1.0
  O  O5  1  0.363  0.271  0.407  1.0
  O  O6  1  0.431  0.748  0.402  1.0
  O  O7  1  0.363  0.272  0.941  1.0
  O  O8  1  0.816  0.482  0.342  1.0
  O  O9  1  0.434  0.768  0.891  1.0
  O  O10  1  0.819  0.503  0.830  1.0
  O  O11  1  0.887  0.979  0.292  1.0
  O  O12  1  0.887  0.978  0.825  1.0
[/CIF]
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The compound described by MgMn4O8 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with four equivalent Mn(1)O5 trigonal bipyramids, edges with four equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(1)O5 trigonal bipyramids. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3) and four equivalent O(1) atoms to form distorted MnO5 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with six equivalent Mn(2)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Mn(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 49-58°. In the second Mn site, Mn(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. There are three 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 a mixture of corner and edge-sharing OMgMn3 trigonal pyramids. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1) and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mn(1) and two equivalent Mn(2) atoms. is represented by the CIF file [CIF]
data_MgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.740
_cell_length_b   5.836
_cell_length_c   5.732
_cell_angle_alpha   60.586
_cell_angle_beta   60.049
_cell_angle_gamma   84.447
_symmetry_Int_Tables_number   1
_cell_volume   142.092
_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  0.625  0.125  0.116  1.0
  Mn  Mn1  1  0.190  0.059  0.867  1.0
  Mn  Mn2  1  0.060  0.191  0.365  1.0
  Mn  Mn3  1  0.625  0.625  0.116  1.0
  Mn  Mn4  1  0.625  0.625  0.616  1.0
  O  O5  1  0.363  0.271  0.407  1.0
  O  O6  1  0.431  0.748  0.402  1.0
  O  O7  1  0.363  0.272  0.941  1.0
  O  O8  1  0.816  0.482  0.342  1.0
  O  O9  1  0.434  0.768  0.891  1.0
  O  O10  1  0.819  0.503  0.830  1.0
  O  O11  1  0.887  0.979  0.292  1.0
  O  O12  1  0.887  0.978  0.825  1.0
[/CIF]
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