The compound described by MgMn4O8 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent Mn(1)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and faces with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-58°. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with four equivalent Mg(1)O6 octahedra, corners with four equivalent Mn(2)O6 octahedra, and corners with eight equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-63°. 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 distorted MnO6 octahedra that share corners with four equivalent Mn(1)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and faces with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-63°. In the third Mn site, Mn(3) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra,  a faceface with one Mg(1)O6 octahedra, and  a faceface with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-60°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mn(1), one Mn(2), and one Mn(3) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(2), and two equivalent Mn(3) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), one Mn(1), one Mn(2), and two equivalent Mn(3) atoms. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Mn(1), and one Mn(3) atom. is represented by the CIF card [CIF]
data_MgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.585
_cell_length_b   5.585
_cell_length_c   6.672
_cell_angle_alpha   53.333
_cell_angle_beta   53.333
_cell_angle_gamma   65.622
_symmetry_Int_Tables_number   1
_cell_volume   133.386
_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  0.893  0.893  0.607  1.0
  Mn  Mn1  1  0.092  0.092  0.908  1.0
  Mn  Mn2  1  0.302  0.302  0.199  1.0
  Mn  Mn3  1  0.606  0.606  0.185  1.0
  Mn  Mn4  1  0.606  0.606  0.604  1.0
  O  O5  1  0.315  0.315  0.470  1.0
  O  O6  1  0.366  0.842  0.396  1.0
  O  O7  1  0.315  0.315  0.901  1.0
  O  O8  1  0.842  0.366  0.396  1.0
  O  O9  1  0.418  0.787  0.898  1.0
  O  O10  1  0.787  0.418  0.898  1.0
  O  O11  1  0.892  0.892  0.315  1.0
  O  O12  1  0.892  0.892  0.901  1.0
[/CIF]
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The compound described by MgMn4O8 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent Mn(1)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and faces with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-58°. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with four equivalent Mg(1)O6 octahedra, corners with four equivalent Mn(2)O6 octahedra, and corners with eight equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-63°. 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 distorted MnO6 octahedra that share corners with four equivalent Mn(1)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and faces with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-63°. In the third Mn site, Mn(3) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra,  a faceface with one Mg(1)O6 octahedra, and  a faceface with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-60°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mn(1), one Mn(2), and one Mn(3) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(2), and two equivalent Mn(3) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), one Mn(1), one Mn(2), and two equivalent Mn(3) atoms. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Mn(1), and one Mn(3) atom. is represented by the CIF card [CIF]
data_MgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.585
_cell_length_b   5.585
_cell_length_c   6.672
_cell_angle_alpha   53.333
_cell_angle_beta   53.333
_cell_angle_gamma   65.622
_symmetry_Int_Tables_number   1
_cell_volume   133.386
_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  0.893  0.893  0.607  1.0
  Mn  Mn1  1  0.092  0.092  0.908  1.0
  Mn  Mn2  1  0.302  0.302  0.199  1.0
  Mn  Mn3  1  0.606  0.606  0.185  1.0
  Mn  Mn4  1  0.606  0.606  0.604  1.0
  O  O5  1  0.315  0.315  0.470  1.0
  O  O6  1  0.366  0.842  0.396  1.0
  O  O7  1  0.315  0.315  0.901  1.0
  O  O8  1  0.842  0.366  0.396  1.0
  O  O9  1  0.418  0.787  0.898  1.0
  O  O10  1  0.787  0.418  0.898  1.0
  O  O11  1  0.892  0.892  0.315  1.0
  O  O12  1  0.892  0.892  0.901  1.0
[/CIF]
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