The compound described by CuCr2O4 is Spinel structured and crystallizes in the orthorhombic Imm2 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 three equivalent Cu(1)O4 tetrahedra, corners with three equivalent Cu(2)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 three equivalent Cu(1)O4 tetrahedra, corners with three equivalent Cu(2)O4 tetrahedra, edges with two equivalent Cr(2)O6 octahedra, and edges with four equivalent Cr(1)O6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form CuO4 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 55-67°. In the second Cu site, Cu(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form CuO4 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 55-67°. 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 Cu(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Cr(2), two equivalent Cr(1), and one Cu(2) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Cr(2), two equivalent Cr(1), and one Cu(1) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Cr(1), two equivalent Cr(2), and one Cu(1) atom. is represented by the CIF card [CIF]
data_Cr2CuO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.888
_cell_length_b   5.887
_cell_length_c   6.099
_cell_angle_alpha   58.840
_cell_angle_beta   58.828
_cell_angle_gamma   85.801
_symmetry_Int_Tables_number   1
_cell_volume   149.218
_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  0.625  0.875  0.750  1.0
  Cr  Cr1  1  0.125  0.375  0.250  1.0
  Cr  Cr2  1  0.625  0.375  0.250  1.0
  Cr  Cr3  1  0.625  0.375  0.750  1.0
  Cu  Cu4  1  0.006  0.994  1.000  1.0
  Cu  Cu5  1  0.255  0.746  0.500  1.0
  O  O6  1  0.407  0.159  0.217  1.0
  O  O7  1  0.373  0.627  0.783  1.0
  O  O8  1  0.874  0.126  0.717  1.0
  O  O9  1  0.840  0.594  0.283  1.0
  O  O10  1  0.841  0.593  0.783  1.0
  O  O11  1  0.373  0.627  0.217  1.0
  O  O12  1  0.874  0.126  0.283  1.0
  O  O13  1  0.406  0.160  0.717  1.0
[/CIF]
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The compound described by CuCr2O4 is Spinel structured and crystallizes in the orthorhombic Imm2 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 three equivalent Cu(1)O4 tetrahedra, corners with three equivalent Cu(2)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 three equivalent Cu(1)O4 tetrahedra, corners with three equivalent Cu(2)O4 tetrahedra, edges with two equivalent Cr(2)O6 octahedra, and edges with four equivalent Cr(1)O6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form CuO4 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 55-67°. In the second Cu site, Cu(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form CuO4 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 55-67°. 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 Cu(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Cr(2), two equivalent Cr(1), and one Cu(2) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Cr(2), two equivalent Cr(1), and one Cu(1) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Cr(1), two equivalent Cr(2), and one Cu(1) atom. is represented by the CIF card [CIF]
data_Cr2CuO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.888
_cell_length_b   5.887
_cell_length_c   6.099
_cell_angle_alpha   58.840
_cell_angle_beta   58.828
_cell_angle_gamma   85.801
_symmetry_Int_Tables_number   1
_cell_volume   149.218
_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  0.625  0.875  0.750  1.0
  Cr  Cr1  1  0.125  0.375  0.250  1.0
  Cr  Cr2  1  0.625  0.375  0.250  1.0
  Cr  Cr3  1  0.625  0.375  0.750  1.0
  Cu  Cu4  1  0.006  0.994  1.000  1.0
  Cu  Cu5  1  0.255  0.746  0.500  1.0
  O  O6  1  0.407  0.159  0.217  1.0
  O  O7  1  0.373  0.627  0.783  1.0
  O  O8  1  0.874  0.126  0.717  1.0
  O  O9  1  0.840  0.594  0.283  1.0
  O  O10  1  0.841  0.593  0.783  1.0
  O  O11  1  0.373  0.627  0.217  1.0
  O  O12  1  0.874  0.126  0.283  1.0
  O  O13  1  0.406  0.160  0.717  1.0
[/CIF]
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