The material described by MgMn2O4 crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. Mn(1) is bonded to one O(2), two equivalent O(3), and three equivalent O(1) atoms to form a mixture of corner and edge-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 0-56°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1) and three equivalent Mn(1) atoms to form distorted OMg2Mn3 trigonal bipyramids that share corners with four equivalent O(3)Mg2Mn4 octahedra, corners with five equivalent O(2)Mg2Mn2 tetrahedra, corners with two equivalent O(1)Mg2Mn3 trigonal bipyramids, edges with three equivalent O(3)Mg2Mn4 octahedra,  an edgeedge with one O(2)Mg2Mn2 tetrahedra, and edges with five equivalent O(1)Mg2Mn3 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 8-44°. In the second O site, O(2) is bonded to two equivalent Mg(1) and two equivalent Mn(1) atoms to form OMg2Mn2 tetrahedra that share corners with two equivalent O(2)Mg2Mn2 tetrahedra, corners with ten equivalent O(1)Mg2Mn3 trigonal bipyramids, edges with four equivalent O(3)Mg2Mn4 octahedra, and edges with two equivalent O(1)Mg2Mn3 trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Mg(1) and four equivalent Mn(1) atoms to form distorted OMg2Mn4 octahedra that share corners with two equivalent O(3)Mg2Mn4 octahedra, corners with eight equivalent O(1)Mg2Mn3 trigonal bipyramids, edges with two equivalent O(3)Mg2Mn4 octahedra, edges with four equivalent O(2)Mg2Mn2 tetrahedra, and edges with six equivalent O(1)Mg2Mn3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 47°. is represented by the CIF card [CIF]
data_MgMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.176
_cell_length_b   5.176
_cell_length_c   9.578
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   146.340
_symmetry_Int_Tables_number   1
_cell_volume   142.226
_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  0.606  0.394  0.750  1.0
  Mg  Mg1  1  0.394  0.606  0.250  1.0
  Mn  Mn2  1  0.134  0.866  0.071  1.0
  Mn  Mn3  1  0.866  0.134  0.929  1.0
  Mn  Mn4  1  0.134  0.866  0.429  1.0
  Mn  Mn5  1  0.866  0.134  0.571  1.0
  O  O6  1  0.781  0.219  0.386  1.0
  O  O7  1  0.219  0.781  0.614  1.0
  O  O8  1  0.219  0.781  0.886  1.0
  O  O9  1  0.781  0.219  0.114  1.0
  O  O10  1  0.042  0.958  0.250  1.0
  O  O11  1  0.958  0.042  0.750  1.0
  O  O12  1  0.500  0.500  0.000  1.0
  O  O13  1  0.500  0.500  0.500  1.0
[/CIF]
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The material described by MgMn2O4 crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. Mn(1) is bonded to one O(2), two equivalent O(3), and three equivalent O(1) atoms to form a mixture of corner and edge-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 0-56°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1) and three equivalent Mn(1) atoms to form distorted OMg2Mn3 trigonal bipyramids that share corners with four equivalent O(3)Mg2Mn4 octahedra, corners with five equivalent O(2)Mg2Mn2 tetrahedra, corners with two equivalent O(1)Mg2Mn3 trigonal bipyramids, edges with three equivalent O(3)Mg2Mn4 octahedra,  an edgeedge with one O(2)Mg2Mn2 tetrahedra, and edges with five equivalent O(1)Mg2Mn3 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 8-44°. In the second O site, O(2) is bonded to two equivalent Mg(1) and two equivalent Mn(1) atoms to form OMg2Mn2 tetrahedra that share corners with two equivalent O(2)Mg2Mn2 tetrahedra, corners with ten equivalent O(1)Mg2Mn3 trigonal bipyramids, edges with four equivalent O(3)Mg2Mn4 octahedra, and edges with two equivalent O(1)Mg2Mn3 trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Mg(1) and four equivalent Mn(1) atoms to form distorted OMg2Mn4 octahedra that share corners with two equivalent O(3)Mg2Mn4 octahedra, corners with eight equivalent O(1)Mg2Mn3 trigonal bipyramids, edges with two equivalent O(3)Mg2Mn4 octahedra, edges with four equivalent O(2)Mg2Mn2 tetrahedra, and edges with six equivalent O(1)Mg2Mn3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 47°. is represented by the CIF card [CIF]
data_MgMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.176
_cell_length_b   5.176
_cell_length_c   9.578
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   146.340
_symmetry_Int_Tables_number   1
_cell_volume   142.226
_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  0.606  0.394  0.750  1.0
  Mg  Mg1  1  0.394  0.606  0.250  1.0
  Mn  Mn2  1  0.134  0.866  0.071  1.0
  Mn  Mn3  1  0.866  0.134  0.929  1.0
  Mn  Mn4  1  0.134  0.866  0.429  1.0
  Mn  Mn5  1  0.866  0.134  0.571  1.0
  O  O6  1  0.781  0.219  0.386  1.0
  O  O7  1  0.219  0.781  0.614  1.0
  O  O8  1  0.219  0.781  0.886  1.0
  O  O9  1  0.781  0.219  0.114  1.0
  O  O10  1  0.042  0.958  0.250  1.0
  O  O11  1  0.958  0.042  0.750  1.0
  O  O12  1  0.500  0.500  0.000  1.0
  O  O13  1  0.500  0.500  0.500  1.0
[/CIF]
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