The compound described by Cr4CuO12 crystallizes in the monoclinic C2 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form CrO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra and corners with two equivalent Cr(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form CrO4 tetrahedra that share corners with two equivalent Cu(1)O6 octahedra and corners with two equivalent Cr(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-51°. Cu(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form CuO6 octahedra that share corners with two equivalent Cr(1)O4 tetrahedra and corners with four equivalent Cr(2)O4 tetrahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one Cu(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Cr(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cr(2) and one Cu(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Cr(2) and one Cu(1) atom. is represented by the CIF card [CIF]
data_Cr4CuO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.731
_cell_length_b   6.731
_cell_length_c   5.760
_cell_angle_alpha   75.623
_cell_angle_beta   104.377
_cell_angle_gamma   95.617
_symmetry_Int_Tables_number   1
_cell_volume   244.699
_cell_formula_units_Z   1
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  0.205  0.611  0.767  1.0
  Cr  Cr1  1  0.389  0.801  0.271  1.0
  Cr  Cr2  1  0.611  0.205  0.733  1.0
  Cr  Cr3  1  0.801  0.389  0.229  1.0
  Cu  Cu4  1  0.911  0.911  0.250  1.0
  O  O5  1  0.030  0.779  0.640  1.0
  O  O6  1  0.097  0.387  0.808  1.0
  O  O7  1  0.204  0.961  0.189  1.0
  O  O8  1  0.358  0.631  0.557  1.0
  O  O9  1  0.387  0.097  0.692  1.0
  O  O10  1  0.354  0.646  0.050  1.0
  O  O11  1  0.631  0.358  0.943  1.0
  O  O12  1  0.622  0.911  0.300  1.0
  O  O13  1  0.646  0.354  0.450  1.0
  O  O14  1  0.779  0.030  0.860  1.0
  O  O15  1  0.911  0.622  0.200  1.0
  O  O16  1  0.961  0.204  0.311  1.0
[/CIF]
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The compound described by Cr4CuO12 crystallizes in the monoclinic C2 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form CrO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra and corners with two equivalent Cr(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form CrO4 tetrahedra that share corners with two equivalent Cu(1)O6 octahedra and corners with two equivalent Cr(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-51°. Cu(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form CuO6 octahedra that share corners with two equivalent Cr(1)O4 tetrahedra and corners with four equivalent Cr(2)O4 tetrahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one Cu(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Cr(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cr(2) and one Cu(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Cr(2) and one Cu(1) atom. is represented by the CIF card [CIF]
data_Cr4CuO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.731
_cell_length_b   6.731
_cell_length_c   5.760
_cell_angle_alpha   75.623
_cell_angle_beta   104.377
_cell_angle_gamma   95.617
_symmetry_Int_Tables_number   1
_cell_volume   244.699
_cell_formula_units_Z   1
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  0.205  0.611  0.767  1.0
  Cr  Cr1  1  0.389  0.801  0.271  1.0
  Cr  Cr2  1  0.611  0.205  0.733  1.0
  Cr  Cr3  1  0.801  0.389  0.229  1.0
  Cu  Cu4  1  0.911  0.911  0.250  1.0
  O  O5  1  0.030  0.779  0.640  1.0
  O  O6  1  0.097  0.387  0.808  1.0
  O  O7  1  0.204  0.961  0.189  1.0
  O  O8  1  0.358  0.631  0.557  1.0
  O  O9  1  0.387  0.097  0.692  1.0
  O  O10  1  0.354  0.646  0.050  1.0
  O  O11  1  0.631  0.358  0.943  1.0
  O  O12  1  0.622  0.911  0.300  1.0
  O  O13  1  0.646  0.354  0.450  1.0
  O  O14  1  0.779  0.030  0.860  1.0
  O  O15  1  0.911  0.622  0.200  1.0
  O  O16  1  0.961  0.204  0.311  1.0
[/CIF]
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