The compound described by NiCr2O4 is Spinel structured and crystallizes in the monoclinic Cc space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form CrO6 octahedra that share corners with six equivalent Ni(1)O4 tetrahedra, edges with two equivalent Cr(1)O6 octahedra, and edges with four equivalent Cr(2)O6 octahedra. In the second Cr site, Cr(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form CrO6 octahedra that share corners with six equivalent Ni(1)O4 tetrahedra, edges with two equivalent Cr(2)O6 octahedra, and edges with four equivalent Cr(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 Cr(1)O6 octahedra and corners with six equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-61°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Cr(1), two equivalent Cr(2), and one Ni(1) atom. In the second O site, O(2) is bonded to one Cr(2), two equivalent Cr(1), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OCr3Ni trigonal pyramids. In the third O site, O(3) is bonded to one Cr(2), two equivalent Cr(1), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OCr3Ni trigonal pyramids. In the fourth O site, O(4) is bonded to one Cr(1), two equivalent Cr(2), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OCr3Ni trigonal pyramids. is represented by the CIF card [CIF]
data_Cr2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.848
_cell_length_b   5.909
_cell_length_c   5.916
_cell_angle_alpha   59.879
_cell_angle_beta   90.147
_cell_angle_gamma   119.753
_symmetry_Int_Tables_number   1
_cell_volume   145.001
_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
  Cr  Cr0  1  0.500  1.000  0.001  1.0
  Cr  Cr1  1  0.001  0.502  0.498  1.0
  Cr  Cr2  1  0.999  0.498  1.000  1.0
  Cr  Cr3  1  1.000  0.000  0.000  1.0
  Ni  Ni4  1  0.627  0.753  0.628  1.0
  Ni  Ni5  1  0.374  0.247  0.381  1.0
  O  O6  1  0.758  0.475  0.758  1.0
  O  O7  1  0.764  0.031  0.759  1.0
  O  O8  1  0.760  0.020  0.219  1.0
  O  O9  1  0.242  0.524  0.235  1.0
  O  O10  1  0.782  0.525  0.234  1.0
  O  O11  1  0.240  0.980  0.239  1.0
  O  O12  1  0.218  0.476  0.759  1.0
  O  O13  1  0.234  0.969  0.790  1.0
[/CIF]
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The compound described by NiCr2O4 is Spinel structured and crystallizes in the monoclinic Cc space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form CrO6 octahedra that share corners with six equivalent Ni(1)O4 tetrahedra, edges with two equivalent Cr(1)O6 octahedra, and edges with four equivalent Cr(2)O6 octahedra. In the second Cr site, Cr(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form CrO6 octahedra that share corners with six equivalent Ni(1)O4 tetrahedra, edges with two equivalent Cr(2)O6 octahedra, and edges with four equivalent Cr(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 Cr(1)O6 octahedra and corners with six equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-61°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Cr(1), two equivalent Cr(2), and one Ni(1) atom. In the second O site, O(2) is bonded to one Cr(2), two equivalent Cr(1), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OCr3Ni trigonal pyramids. In the third O site, O(3) is bonded to one Cr(2), two equivalent Cr(1), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OCr3Ni trigonal pyramids. In the fourth O site, O(4) is bonded to one Cr(1), two equivalent Cr(2), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OCr3Ni trigonal pyramids. is represented by the CIF card [CIF]
data_Cr2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.848
_cell_length_b   5.909
_cell_length_c   5.916
_cell_angle_alpha   59.879
_cell_angle_beta   90.147
_cell_angle_gamma   119.753
_symmetry_Int_Tables_number   1
_cell_volume   145.001
_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
  Cr  Cr0  1  0.500  1.000  0.001  1.0
  Cr  Cr1  1  0.001  0.502  0.498  1.0
  Cr  Cr2  1  0.999  0.498  1.000  1.0
  Cr  Cr3  1  1.000  0.000  0.000  1.0
  Ni  Ni4  1  0.627  0.753  0.628  1.0
  Ni  Ni5  1  0.374  0.247  0.381  1.0
  O  O6  1  0.758  0.475  0.758  1.0
  O  O7  1  0.764  0.031  0.759  1.0
  O  O8  1  0.760  0.020  0.219  1.0
  O  O9  1  0.242  0.524  0.235  1.0
  O  O10  1  0.782  0.525  0.234  1.0
  O  O11  1  0.240  0.980  0.239  1.0
  O  O12  1  0.218  0.476  0.759  1.0
  O  O13  1  0.234  0.969  0.790  1.0
[/CIF]
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