The material described by NiMn2O4 is Spinel structured and crystallizes in the tetragonal I4_1md space group. Mn(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Ni(1)O4 tetrahedra and edges with six equivalent Mn(1)O6 octahedra. Ni(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form NiO4 tetrahedra that share corners with twelve equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-59°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Mn(1) and one Ni(1) atom. In the second O site, O(2) is bonded to three equivalent Mn(1) and one Ni(1) atom to form a mixture of distorted corner and edge-sharing OMn3Ni trigonal pyramids. is represented by the CIF card [CIF]
data_Mn2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.195
_cell_length_b   6.195
_cell_length_c   6.195
_cell_angle_alpha   123.646
_cell_angle_beta   123.646
_cell_angle_gamma   83.792
_symmetry_Int_Tables_number   1
_cell_volume   157.836
_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
  Mn  Mn0  1  0.375  0.625  0.750  1.0
  Mn  Mn1  1  0.375  0.125  0.750  1.0
  Mn  Mn2  1  0.375  0.625  0.250  1.0
  Mn  Mn3  1  0.875  0.625  0.250  1.0
  Ni  Ni4  1  0.750  0.250  0.500  1.0
  Ni  Ni5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.600  0.878  0.722  1.0
  O  O7  1  0.628  0.406  0.778  1.0
  O  O8  1  0.611  0.383  0.228  1.0
  O  O9  1  0.628  0.850  0.222  1.0
  O  O10  1  0.156  0.878  0.278  1.0
  O  O11  1  0.133  0.405  0.272  1.0
  O  O12  1  0.155  0.383  0.772  1.0
  O  O13  1  0.133  0.861  0.728  1.0
[/CIF]
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The material described by NiMn2O4 is Spinel structured and crystallizes in the tetragonal I4_1md space group. Mn(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Ni(1)O4 tetrahedra and edges with six equivalent Mn(1)O6 octahedra. Ni(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form NiO4 tetrahedra that share corners with twelve equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-59°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Mn(1) and one Ni(1) atom. In the second O site, O(2) is bonded to three equivalent Mn(1) and one Ni(1) atom to form a mixture of distorted corner and edge-sharing OMn3Ni trigonal pyramids. is represented by the CIF card [CIF]
data_Mn2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.195
_cell_length_b   6.195
_cell_length_c   6.195
_cell_angle_alpha   123.646
_cell_angle_beta   123.646
_cell_angle_gamma   83.792
_symmetry_Int_Tables_number   1
_cell_volume   157.836
_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
  Mn  Mn0  1  0.375  0.625  0.750  1.0
  Mn  Mn1  1  0.375  0.125  0.750  1.0
  Mn  Mn2  1  0.375  0.625  0.250  1.0
  Mn  Mn3  1  0.875  0.625  0.250  1.0
  Ni  Ni4  1  0.750  0.250  0.500  1.0
  Ni  Ni5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.600  0.878  0.722  1.0
  O  O7  1  0.628  0.406  0.778  1.0
  O  O8  1  0.611  0.383  0.228  1.0
  O  O9  1  0.628  0.850  0.222  1.0
  O  O10  1  0.156  0.878  0.278  1.0
  O  O11  1  0.133  0.405  0.272  1.0
  O  O12  1  0.155  0.383  0.772  1.0
  O  O13  1  0.133  0.861  0.728  1.0
[/CIF]
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