The material described by Ca(CuO2)2 is Spinel-like structured and crystallizes in the trigonal R3m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(3) and three equivalent O(4) atoms to form CaO4 tetrahedra that share corners with nine equivalent Cu(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-61°. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(4) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2) and three equivalent O(1) atoms to form corner-sharing CuO4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-58°. In the second Cu site, Cu(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form CuO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Cu(1)O4 tetrahedra, and edges with four equivalent Cu(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ca(2), one Cu(1), and two equivalent Cu(2) atoms to form distorted OCaCu3 trigonal pyramids that share corners with seven equivalent O(4)Ca2Cu2 tetrahedra, corners with two equivalent O(1)CaCu3 trigonal pyramids, and edges with two equivalent O(1)CaCu3 trigonal pyramids. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Cu(1) and three equivalent Cu(2) atoms. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Ca(1) and three equivalent Cu(2) atoms. In the fourth O site, O(4) is bonded to one Ca(1), one Ca(2), and two equivalent Cu(2) atoms to form OCa2Cu2 tetrahedra that share corners with two equivalent O(4)Ca2Cu2 tetrahedra, corners with seven equivalent O(1)CaCu3 trigonal pyramids, and edges with two equivalent O(4)Ca2Cu2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca(CuO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.331
_cell_length_b   6.331
_cell_length_c   6.331
_cell_angle_alpha   58.272
_cell_angle_beta   58.272
_cell_angle_gamma   58.272
_symmetry_Int_Tables_number   1
_cell_volume   172.310
_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
  Ca  Ca0  1  0.021  0.021  0.021  1.0
  Ca  Ca1  1  0.623  0.623  0.623  1.0
  Cu  Cu2  1  0.238  0.238  0.238  1.0
  Cu  Cu3  1  0.631  0.121  0.631  1.0
  Cu  Cu4  1  0.631  0.631  0.121  1.0
  Cu  Cu5  1  0.121  0.631  0.631  1.0
  O  O6  1  0.825  0.363  0.363  1.0
  O  O7  1  0.363  0.363  0.825  1.0
  O  O8  1  0.363  0.825  0.363  1.0
  O  O9  1  0.356  0.356  0.356  1.0
  O  O10  1  0.878  0.878  0.878  1.0
  O  O11  1  0.874  0.451  0.874  1.0
  O  O12  1  0.874  0.874  0.451  1.0
  O  O13  1  0.451  0.874  0.874  1.0
[/CIF]
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The material described by Ca(CuO2)2 is Spinel-like structured and crystallizes in the trigonal R3m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(3) and three equivalent O(4) atoms to form CaO4 tetrahedra that share corners with nine equivalent Cu(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-61°. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(4) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2) and three equivalent O(1) atoms to form corner-sharing CuO4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-58°. In the second Cu site, Cu(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form CuO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Cu(1)O4 tetrahedra, and edges with four equivalent Cu(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ca(2), one Cu(1), and two equivalent Cu(2) atoms to form distorted OCaCu3 trigonal pyramids that share corners with seven equivalent O(4)Ca2Cu2 tetrahedra, corners with two equivalent O(1)CaCu3 trigonal pyramids, and edges with two equivalent O(1)CaCu3 trigonal pyramids. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Cu(1) and three equivalent Cu(2) atoms. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Ca(1) and three equivalent Cu(2) atoms. In the fourth O site, O(4) is bonded to one Ca(1), one Ca(2), and two equivalent Cu(2) atoms to form OCa2Cu2 tetrahedra that share corners with two equivalent O(4)Ca2Cu2 tetrahedra, corners with seven equivalent O(1)CaCu3 trigonal pyramids, and edges with two equivalent O(4)Ca2Cu2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca(CuO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.331
_cell_length_b   6.331
_cell_length_c   6.331
_cell_angle_alpha   58.272
_cell_angle_beta   58.272
_cell_angle_gamma   58.272
_symmetry_Int_Tables_number   1
_cell_volume   172.310
_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
  Ca  Ca0  1  0.021  0.021  0.021  1.0
  Ca  Ca1  1  0.623  0.623  0.623  1.0
  Cu  Cu2  1  0.238  0.238  0.238  1.0
  Cu  Cu3  1  0.631  0.121  0.631  1.0
  Cu  Cu4  1  0.631  0.631  0.121  1.0
  Cu  Cu5  1  0.121  0.631  0.631  1.0
  O  O6  1  0.825  0.363  0.363  1.0
  O  O7  1  0.363  0.363  0.825  1.0
  O  O8  1  0.363  0.825  0.363  1.0
  O  O9  1  0.356  0.356  0.356  1.0
  O  O10  1  0.878  0.878  0.878  1.0
  O  O11  1  0.874  0.451  0.874  1.0
  O  O12  1  0.874  0.874  0.451  1.0
  O  O13  1  0.451  0.874  0.874  1.0
[/CIF]
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