The crystal structure described by NiMn2O4 is Spinel structured and crystallizes in the monoclinic Cc space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Ni(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) 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 six equivalent Ni(1)O4 tetrahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. Ni(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form NiO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra and corners with six equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-59°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mn(2), two equivalent Mn(1), and one Ni(1) atom. In the second O site, O(2) is bonded to one Mn(1), two equivalent Mn(2), and one Ni(1) atom to form a mixture of distorted corner and edge-sharing OMn3Ni trigonal pyramids. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Mn(1), two equivalent Mn(2), and one Ni(1) atom. In the fourth O site, O(4) is bonded to one Mn(2), two 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 file [CIF]
data_Mn2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.850
_cell_length_b   5.850
_cell_length_c   6.190
_cell_angle_alpha   61.823
_cell_angle_beta   61.823
_cell_angle_gamma   89.889
_symmetry_Int_Tables_number   1
_cell_volume   157.835
_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  0.502  1.000  0.996  1.0
  Mn  Mn1  1  1.000  0.502  0.496  1.0
  Mn  Mn2  1  0.502  0.502  0.498  1.0
  Mn  Mn3  1  0.502  0.502  0.998  1.0
  Ni  Ni4  1  0.879  0.128  0.244  1.0
  Ni  Ni5  1  0.128  0.879  0.744  1.0
  O  O6  1  0.250  0.723  0.498  1.0
  O  O7  1  0.723  0.250  0.998  1.0
  O  O8  1  0.745  0.724  0.509  1.0
  O  O9  1  0.280  0.251  0.997  1.0
  O  O10  1  0.251  0.280  0.497  1.0
  O  O11  1  0.724  0.745  0.009  1.0
  O  O12  1  0.746  0.269  0.508  1.0
  O  O13  1  0.269  0.746  0.008  1.0
[/CIF]
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The crystal structure described by NiMn2O4 is Spinel structured and crystallizes in the monoclinic Cc space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Ni(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) 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 six equivalent Ni(1)O4 tetrahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. Ni(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form NiO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra and corners with six equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-59°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mn(2), two equivalent Mn(1), and one Ni(1) atom. In the second O site, O(2) is bonded to one Mn(1), two equivalent Mn(2), and one Ni(1) atom to form a mixture of distorted corner and edge-sharing OMn3Ni trigonal pyramids. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Mn(1), two equivalent Mn(2), and one Ni(1) atom. In the fourth O site, O(4) is bonded to one Mn(2), two 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 file [CIF]
data_Mn2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.850
_cell_length_b   5.850
_cell_length_c   6.190
_cell_angle_alpha   61.823
_cell_angle_beta   61.823
_cell_angle_gamma   89.889
_symmetry_Int_Tables_number   1
_cell_volume   157.835
_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  0.502  1.000  0.996  1.0
  Mn  Mn1  1  1.000  0.502  0.496  1.0
  Mn  Mn2  1  0.502  0.502  0.498  1.0
  Mn  Mn3  1  0.502  0.502  0.998  1.0
  Ni  Ni4  1  0.879  0.128  0.244  1.0
  Ni  Ni5  1  0.128  0.879  0.744  1.0
  O  O6  1  0.250  0.723  0.498  1.0
  O  O7  1  0.723  0.250  0.998  1.0
  O  O8  1  0.745  0.724  0.509  1.0
  O  O9  1  0.280  0.251  0.997  1.0
  O  O10  1  0.251  0.280  0.497  1.0
  O  O11  1  0.724  0.745  0.009  1.0
  O  O12  1  0.746  0.269  0.508  1.0
  O  O13  1  0.269  0.746  0.008  1.0
[/CIF]
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