The crystal structure described by CaCuO2 crystallizes in the triclinic P-1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(4), two equivalent O(3), and three equivalent O(1) atoms to form edge-sharing CaO6 octahedra. In the second Ca site, Ca(2) is bonded in a 7-coordinate geometry to two equivalent O(2), two equivalent O(4), and three equivalent O(3) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted trigonal planar geometry to one O(2) and two equivalent O(1) atoms. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Ca(1) and two equivalent Cu(1) atoms to form OCa3Cu2 square pyramids that share corners with three equivalent O(4)Ca3Cu2 square pyramids, corners with four equivalent O(3)Ca5 square pyramids,  an edgeedge with one O(3)Ca5 square pyramid, and edges with four equivalent O(1)Ca3Cu2 square pyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Ca(2), one Cu(1), and two equivalent Cu(2) atoms. In the third O site, O(3) is bonded to two equivalent Ca(1) and three equivalent Ca(2) atoms to form distorted OCa5 square pyramids that share corners with two equivalent O(4)Ca3Cu2 square pyramids, corners with four equivalent O(1)Ca3Cu2 square pyramids,  an edgeedge with one O(1)Ca3Cu2 square pyramid, edges with three equivalent O(4)Ca3Cu2 square pyramids, and edges with four equivalent O(3)Ca5 square pyramids. In the fourth O site, O(4) is bonded to one Ca(1), two equivalent Ca(2), and two equivalent Cu(2) atoms to form distorted OCa3Cu2 square pyramids that share corners with two equivalent O(3)Ca5 square pyramids, corners with three equivalent O(1)Ca3Cu2 square pyramids, edges with two equivalent O(4)Ca3Cu2 square pyramids, and edges with three equivalent O(3)Ca5 square pyramids. is represented by the CIF card [CIF]
data_CaCuO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.038
_cell_length_b   8.248
_cell_length_c   8.603
_cell_angle_alpha   94.789
_cell_angle_beta   89.471
_cell_angle_gamma   99.687
_symmetry_Int_Tables_number   1
_cell_volume   211.763
_cell_formula_units_Z   4
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
  Ca  Ca0  1  0.213  0.919  0.821  1.0
  Ca  Ca1  1  0.787  0.081  0.179  1.0
  Ca  Ca2  1  0.338  0.188  0.546  1.0
  Ca  Ca3  1  0.662  0.812  0.454  1.0
  Cu  Cu4  1  0.114  0.728  0.105  1.0
  Cu  Cu5  1  0.556  0.552  0.688  1.0
  Cu  Cu6  1  0.444  0.448  0.312  1.0
  Cu  Cu7  1  0.886  0.272  0.895  1.0
  O  O8  1  0.339  0.176  0.998  1.0
  O  O9  1  0.017  0.594  0.269  1.0
  O  O10  1  0.983  0.406  0.731  1.0
  O  O11  1  0.661  0.824  0.002  1.0
  O  O12  1  0.236  0.973  0.341  1.0
  O  O13  1  0.117  0.690  0.636  1.0
  O  O14  1  0.764  0.027  0.659  1.0
  O  O15  1  0.883  0.310  0.364  1.0
[/CIF]
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The crystal structure described by CaCuO2 crystallizes in the triclinic P-1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(4), two equivalent O(3), and three equivalent O(1) atoms to form edge-sharing CaO6 octahedra. In the second Ca site, Ca(2) is bonded in a 7-coordinate geometry to two equivalent O(2), two equivalent O(4), and three equivalent O(3) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted trigonal planar geometry to one O(2) and two equivalent O(1) atoms. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Ca(1) and two equivalent Cu(1) atoms to form OCa3Cu2 square pyramids that share corners with three equivalent O(4)Ca3Cu2 square pyramids, corners with four equivalent O(3)Ca5 square pyramids,  an edgeedge with one O(3)Ca5 square pyramid, and edges with four equivalent O(1)Ca3Cu2 square pyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Ca(2), one Cu(1), and two equivalent Cu(2) atoms. In the third O site, O(3) is bonded to two equivalent Ca(1) and three equivalent Ca(2) atoms to form distorted OCa5 square pyramids that share corners with two equivalent O(4)Ca3Cu2 square pyramids, corners with four equivalent O(1)Ca3Cu2 square pyramids,  an edgeedge with one O(1)Ca3Cu2 square pyramid, edges with three equivalent O(4)Ca3Cu2 square pyramids, and edges with four equivalent O(3)Ca5 square pyramids. In the fourth O site, O(4) is bonded to one Ca(1), two equivalent Ca(2), and two equivalent Cu(2) atoms to form distorted OCa3Cu2 square pyramids that share corners with two equivalent O(3)Ca5 square pyramids, corners with three equivalent O(1)Ca3Cu2 square pyramids, edges with two equivalent O(4)Ca3Cu2 square pyramids, and edges with three equivalent O(3)Ca5 square pyramids. is represented by the CIF card [CIF]
data_CaCuO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.038
_cell_length_b   8.248
_cell_length_c   8.603
_cell_angle_alpha   94.789
_cell_angle_beta   89.471
_cell_angle_gamma   99.687
_symmetry_Int_Tables_number   1
_cell_volume   211.763
_cell_formula_units_Z   4
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
  Ca  Ca0  1  0.213  0.919  0.821  1.0
  Ca  Ca1  1  0.787  0.081  0.179  1.0
  Ca  Ca2  1  0.338  0.188  0.546  1.0
  Ca  Ca3  1  0.662  0.812  0.454  1.0
  Cu  Cu4  1  0.114  0.728  0.105  1.0
  Cu  Cu5  1  0.556  0.552  0.688  1.0
  Cu  Cu6  1  0.444  0.448  0.312  1.0
  Cu  Cu7  1  0.886  0.272  0.895  1.0
  O  O8  1  0.339  0.176  0.998  1.0
  O  O9  1  0.017  0.594  0.269  1.0
  O  O10  1  0.983  0.406  0.731  1.0
  O  O11  1  0.661  0.824  0.002  1.0
  O  O12  1  0.236  0.973  0.341  1.0
  O  O13  1  0.117  0.690  0.636  1.0
  O  O14  1  0.764  0.027  0.659  1.0
  O  O15  1  0.883  0.310  0.364  1.0
[/CIF]
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