The crystal structure described by MgMn2(NiO3)2 crystallizes in the trigonal R-3 space group. Mg(1) is bonded to six equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with six equivalent Ni(1)O6 octahedra, and faces with two equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 42°. Mn(1) is bonded to six equivalent O(1) atoms to form MnO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with nine equivalent Ni(1)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra,  a faceface with one Mg(1)O6 octahedra, and  a faceface with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-55°. Ni(1) is bonded to six equivalent O(1) atoms to form distorted NiO6 octahedra that share corners with nine equivalent Mn(1)O6 octahedra, edges with three equivalent Mg(1)O6 octahedra, edges with three equivalent Ni(1)O6 octahedra, and  a faceface with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-55°. O(1) is bonded to one Mg(1), two equivalent Mn(1), and two equivalent Ni(1) atoms to form a mixture of distorted corner and edge-sharing OMgMn2Ni2 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn2(NiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.815
_cell_length_b   5.815
_cell_length_c   5.815
_cell_angle_alpha   52.393
_cell_angle_beta   52.393
_cell_angle_gamma   52.393
_symmetry_Int_Tables_number   1
_cell_volume   114.219
_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  0.000  0.000  0.000  1.0
  Mn  Mn1  1  0.827  0.827  0.827  1.0
  Mn  Mn2  1  0.173  0.173  0.173  1.0
  Ni  Ni3  1  0.644  0.644  0.644  1.0
  Ni  Ni4  1  0.356  0.356  0.356  1.0
  O  O5  1  0.772  0.416  0.056  1.0
  O  O6  1  0.416  0.056  0.772  1.0
  O  O7  1  0.056  0.772  0.416  1.0
  O  O8  1  0.228  0.584  0.944  1.0
  O  O9  1  0.944  0.228  0.584  1.0
  O  O10  1  0.584  0.944  0.228  1.0
[/CIF]
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The crystal structure described by MgMn2(NiO3)2 crystallizes in the trigonal R-3 space group. Mg(1) is bonded to six equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with six equivalent Ni(1)O6 octahedra, and faces with two equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 42°. Mn(1) is bonded to six equivalent O(1) atoms to form MnO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with nine equivalent Ni(1)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra,  a faceface with one Mg(1)O6 octahedra, and  a faceface with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-55°. Ni(1) is bonded to six equivalent O(1) atoms to form distorted NiO6 octahedra that share corners with nine equivalent Mn(1)O6 octahedra, edges with three equivalent Mg(1)O6 octahedra, edges with three equivalent Ni(1)O6 octahedra, and  a faceface with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-55°. O(1) is bonded to one Mg(1), two equivalent Mn(1), and two equivalent Ni(1) atoms to form a mixture of distorted corner and edge-sharing OMgMn2Ni2 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn2(NiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.815
_cell_length_b   5.815
_cell_length_c   5.815
_cell_angle_alpha   52.393
_cell_angle_beta   52.393
_cell_angle_gamma   52.393
_symmetry_Int_Tables_number   1
_cell_volume   114.219
_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  0.000  0.000  0.000  1.0
  Mn  Mn1  1  0.827  0.827  0.827  1.0
  Mn  Mn2  1  0.173  0.173  0.173  1.0
  Ni  Ni3  1  0.644  0.644  0.644  1.0
  Ni  Ni4  1  0.356  0.356  0.356  1.0
  O  O5  1  0.772  0.416  0.056  1.0
  O  O6  1  0.416  0.056  0.772  1.0
  O  O7  1  0.056  0.772  0.416  1.0
  O  O8  1  0.228  0.584  0.944  1.0
  O  O9  1  0.944  0.228  0.584  1.0
  O  O10  1  0.584  0.944  0.228  1.0
[/CIF]
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