The structure described by MgMn4NiO8 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, 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 two equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-17°. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Mn(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-12°. In the second Mn site, Mn(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-12°. In the third Mn site, Mn(3) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. In the fourth Mn site, Mn(4) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form MnO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, 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 two equivalent Ni(1)O6 octahedra. Ni(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NiO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, 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 two equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-17°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a see-saw-like geometry to one Mg(1), one Mn(3), one Mn(4), and one Ni(1) atom. In the second O site, O(2) is bonded to one Mg(1), one Mn(1), one Mn(2), one Mn(4), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgMn3Ni square pyramids. In the third O site, O(3) is bonded to one Mg(1), one Mn(1), one Mn(2), one Mn(3), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgMn3Ni square pyramids. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mn(1), one Mn(2), one Mn(3), and one Mn(4) atom. is represented by the CIF file [CIF]
data_MgMn4NiO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.944
_cell_length_b   6.007
_cell_length_c   6.064
_cell_angle_alpha   92.942
_cell_angle_beta   61.847
_cell_angle_gamma   61.439
_symmetry_Int_Tables_number   1
_cell_volume   156.586
_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  0.000  0.500  1.0
  Mn  Mn1  1  0.000  0.500  0.500  1.0
  Mn  Mn2  1  0.000  0.000  0.000  1.0
  Mn  Mn3  1  0.500  0.000  0.000  1.0
  Mn  Mn4  1  0.000  0.500  0.000  1.0
  Ni  Ni5  1  0.500  0.500  0.000  1.0
  O  O6  1  0.457  0.245  0.801  1.0
  O  O7  1  0.002  0.266  0.765  1.0
  O  O8  1  0.501  0.768  0.764  1.0
  O  O9  1  0.949  0.782  0.778  1.0
  O  O10  1  0.051  0.218  0.222  1.0
  O  O11  1  0.499  0.232  0.236  1.0
  O  O12  1  0.998  0.734  0.235  1.0
  O  O13  1  0.543  0.755  0.199  1.0
[/CIF]
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The structure described by MgMn4NiO8 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, 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 two equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-17°. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Mn(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-12°. In the second Mn site, Mn(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-12°. In the third Mn site, Mn(3) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. In the fourth Mn site, Mn(4) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form MnO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, 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 two equivalent Ni(1)O6 octahedra. Ni(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NiO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, 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 two equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-17°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a see-saw-like geometry to one Mg(1), one Mn(3), one Mn(4), and one Ni(1) atom. In the second O site, O(2) is bonded to one Mg(1), one Mn(1), one Mn(2), one Mn(4), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgMn3Ni square pyramids. In the third O site, O(3) is bonded to one Mg(1), one Mn(1), one Mn(2), one Mn(3), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgMn3Ni square pyramids. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mn(1), one Mn(2), one Mn(3), and one Mn(4) atom. is represented by the CIF file [CIF]
data_MgMn4NiO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.944
_cell_length_b   6.007
_cell_length_c   6.064
_cell_angle_alpha   92.942
_cell_angle_beta   61.847
_cell_angle_gamma   61.439
_symmetry_Int_Tables_number   1
_cell_volume   156.586
_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  0.000  0.500  1.0
  Mn  Mn1  1  0.000  0.500  0.500  1.0
  Mn  Mn2  1  0.000  0.000  0.000  1.0
  Mn  Mn3  1  0.500  0.000  0.000  1.0
  Mn  Mn4  1  0.000  0.500  0.000  1.0
  Ni  Ni5  1  0.500  0.500  0.000  1.0
  O  O6  1  0.457  0.245  0.801  1.0
  O  O7  1  0.002  0.266  0.765  1.0
  O  O8  1  0.501  0.768  0.764  1.0
  O  O9  1  0.949  0.782  0.778  1.0
  O  O10  1  0.051  0.218  0.222  1.0
  O  O11  1  0.499  0.232  0.236  1.0
  O  O12  1  0.998  0.734  0.235  1.0
  O  O13  1  0.543  0.755  0.199  1.0
[/CIF]
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