The compound described by NiMnO3 crystallizes in the triclinic P-1 space group. Mn(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form MnO5 trigonal bipyramids that share corners with two equivalent Ni(1)O6 octahedra, corners with two equivalent Mn(1)O5 trigonal bipyramids, edges with four equivalent Ni(1)O6 octahedra, and  an edgeedge with one Mn(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 36-60°. 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 two equivalent Ni(1)O6 octahedra, corners with two equivalent Mn(1)O5 trigonal bipyramids, edges with two equivalent Ni(1)O6 octahedra, and edges with four equivalent Mn(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 20°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mn(1) and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a see-saw-like geometry to two equivalent Mn(1) and two equivalent Ni(1) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mn(1) and two equivalent Ni(1) atoms. is represented by the CIF file [CIF]
data_MnNiO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.174
_cell_length_b   5.722
_cell_length_c   6.112
_cell_angle_alpha   117.177
_cell_angle_beta   144.616
_cell_angle_gamma   35.547
_symmetry_Int_Tables_number   1
_cell_volume   113.168
_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  0.666  0.653  0.820  1.0
  Mn  Mn1  1  0.334  0.347  0.180  1.0
  Ni  Ni2  1  0.009  0.231  0.748  1.0
  Ni  Ni3  1  0.991  0.769  0.252  1.0
  O  O4  1  0.856  0.817  0.735  1.0
  O  O5  1  0.489  0.219  0.690  1.0
  O  O6  1  0.151  0.685  0.774  1.0
  O  O7  1  0.144  0.183  0.265  1.0
  O  O8  1  0.511  0.781  0.310  1.0
  O  O9  1  0.849  0.315  0.226  1.0
[/CIF]
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The compound described by NiMnO3 crystallizes in the triclinic P-1 space group. Mn(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form MnO5 trigonal bipyramids that share corners with two equivalent Ni(1)O6 octahedra, corners with two equivalent Mn(1)O5 trigonal bipyramids, edges with four equivalent Ni(1)O6 octahedra, and  an edgeedge with one Mn(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 36-60°. 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 two equivalent Ni(1)O6 octahedra, corners with two equivalent Mn(1)O5 trigonal bipyramids, edges with two equivalent Ni(1)O6 octahedra, and edges with four equivalent Mn(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 20°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mn(1) and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a see-saw-like geometry to two equivalent Mn(1) and two equivalent Ni(1) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mn(1) and two equivalent Ni(1) atoms. is represented by the CIF file [CIF]
data_MnNiO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.174
_cell_length_b   5.722
_cell_length_c   6.112
_cell_angle_alpha   117.177
_cell_angle_beta   144.616
_cell_angle_gamma   35.547
_symmetry_Int_Tables_number   1
_cell_volume   113.168
_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  0.666  0.653  0.820  1.0
  Mn  Mn1  1  0.334  0.347  0.180  1.0
  Ni  Ni2  1  0.009  0.231  0.748  1.0
  Ni  Ni3  1  0.991  0.769  0.252  1.0
  O  O4  1  0.856  0.817  0.735  1.0
  O  O5  1  0.489  0.219  0.690  1.0
  O  O6  1  0.151  0.685  0.774  1.0
  O  O7  1  0.144  0.183  0.265  1.0
  O  O8  1  0.511  0.781  0.310  1.0
  O  O9  1  0.849  0.315  0.226  1.0
[/CIF]
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