The material described by Ca3Cu2O6 crystallizes in the monoclinic Cm space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(5), two equivalent O(3), and two equivalent O(4) atoms. In the second Ca site, Ca(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(6), two equivalent O(3), and two equivalent O(4) atoms. In the third Ca site, Ca(3) is bonded to one O(1), one O(2), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form distorted edge-sharing CaO7 hexagonal pyramids. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to one O(4), one O(5), and two equivalent O(1) atoms. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to one O(3), one O(6), and two equivalent O(2) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ca(2), one Ca(3), and two equivalent Cu(1) atoms to form distorted OCa3Cu2 trigonal bipyramids that share  a cornercorner with one O(4)Ca5Cu octahedra, corners with four equivalent O(3)Ca4Cu square pyramids,  a cornercorner with one O(2)Ca3Cu2 trigonal bipyramid, corners with two equivalent O(1)Ca3Cu2 trigonal bipyramids,  an edgeedge with one O(2)Ca3Cu2 trigonal bipyramid, and faces with two equivalent O(4)Ca5Cu octahedra. The corner-sharing octahedral tilt angles are 39°. In the second O site, O(2) is bonded to one Ca(1), one Ca(2), one Ca(3), and two equivalent Cu(2) atoms to form distorted OCa3Cu2 trigonal bipyramids that share corners with five equivalent O(4)Ca5Cu octahedra,  a cornercorner with one O(1)Ca3Cu2 trigonal bipyramid, corners with two equivalent O(2)Ca3Cu2 trigonal bipyramids,  an edgeedge with one O(1)Ca3Cu2 trigonal bipyramid, and faces with two equivalent O(3)Ca4Cu square pyramids. The corner-sharing octahedral tilt angles range from 39-64°. In the third O site, O(3) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Cu(2) atom to form OCa4Cu square pyramids that share corners with four equivalent O(4)Ca5Cu octahedra, corners with four equivalent O(1)Ca3Cu2 trigonal bipyramids, edges with two equivalent O(4)Ca5Cu octahedra, edges with two equivalent O(3)Ca4Cu square pyramids, and faces with two equivalent O(2)Ca3Cu2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 5-6°. In the fourth O site, O(4) is bonded to one Ca(3), two equivalent Ca(1), two equivalent Ca(2), and one Cu(1) atom to form OCa5Cu octahedra that share corners with four equivalent O(3)Ca4Cu square pyramids,  a cornercorner with one O(1)Ca3Cu2 trigonal bipyramid, corners with five equivalent O(2)Ca3Cu2 trigonal bipyramids, edges with two equivalent O(4)Ca5Cu octahedra, edges with two equivalent O(3)Ca4Cu square pyramids, and faces with two equivalent O(1)Ca3Cu2 trigonal bipyramids. In the fifth O site, O(5) is bonded in a see-saw-like geometry to one Ca(1), two equivalent Ca(3), and one Cu(1) atom. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Ca(2), two equivalent Ca(3), and one Cu(2) atom. is represented by the CIF card [CIF]
data_Ca3(CuO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.565
_cell_length_b   6.565
_cell_length_c   6.780
_cell_angle_alpha   74.857
_cell_angle_beta   74.857
_cell_angle_gamma   32.786
_symmetry_Int_Tables_number   1
_cell_volume   152.248
_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
  Ca  Ca0  1  0.843  0.843  0.820  1.0
  Ca  Ca1  1  0.842  0.842  0.340  1.0
  Ca  Ca2  1  0.148  0.148  0.173  1.0
  Cu  Cu3  1  0.507  0.507  0.984  1.0
  Cu  Cu4  1  0.513  0.513  0.506  1.0
  O  O5  1  0.987  0.987  0.025  1.0
  O  O6  1  0.991  0.991  0.486  1.0
  O  O7  1  0.357  0.357  0.584  1.0
  O  O8  1  0.346  0.346  0.067  1.0
  O  O9  1  0.655  0.655  0.954  1.0
  O  O10  1  0.661  0.661  0.386  1.0
[/CIF]
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The material described by Ca3Cu2O6 crystallizes in the monoclinic Cm space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(5), two equivalent O(3), and two equivalent O(4) atoms. In the second Ca site, Ca(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(6), two equivalent O(3), and two equivalent O(4) atoms. In the third Ca site, Ca(3) is bonded to one O(1), one O(2), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form distorted edge-sharing CaO7 hexagonal pyramids. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to one O(4), one O(5), and two equivalent O(1) atoms. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to one O(3), one O(6), and two equivalent O(2) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ca(2), one Ca(3), and two equivalent Cu(1) atoms to form distorted OCa3Cu2 trigonal bipyramids that share  a cornercorner with one O(4)Ca5Cu octahedra, corners with four equivalent O(3)Ca4Cu square pyramids,  a cornercorner with one O(2)Ca3Cu2 trigonal bipyramid, corners with two equivalent O(1)Ca3Cu2 trigonal bipyramids,  an edgeedge with one O(2)Ca3Cu2 trigonal bipyramid, and faces with two equivalent O(4)Ca5Cu octahedra. The corner-sharing octahedral tilt angles are 39°. In the second O site, O(2) is bonded to one Ca(1), one Ca(2), one Ca(3), and two equivalent Cu(2) atoms to form distorted OCa3Cu2 trigonal bipyramids that share corners with five equivalent O(4)Ca5Cu octahedra,  a cornercorner with one O(1)Ca3Cu2 trigonal bipyramid, corners with two equivalent O(2)Ca3Cu2 trigonal bipyramids,  an edgeedge with one O(1)Ca3Cu2 trigonal bipyramid, and faces with two equivalent O(3)Ca4Cu square pyramids. The corner-sharing octahedral tilt angles range from 39-64°. In the third O site, O(3) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Cu(2) atom to form OCa4Cu square pyramids that share corners with four equivalent O(4)Ca5Cu octahedra, corners with four equivalent O(1)Ca3Cu2 trigonal bipyramids, edges with two equivalent O(4)Ca5Cu octahedra, edges with two equivalent O(3)Ca4Cu square pyramids, and faces with two equivalent O(2)Ca3Cu2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 5-6°. In the fourth O site, O(4) is bonded to one Ca(3), two equivalent Ca(1), two equivalent Ca(2), and one Cu(1) atom to form OCa5Cu octahedra that share corners with four equivalent O(3)Ca4Cu square pyramids,  a cornercorner with one O(1)Ca3Cu2 trigonal bipyramid, corners with five equivalent O(2)Ca3Cu2 trigonal bipyramids, edges with two equivalent O(4)Ca5Cu octahedra, edges with two equivalent O(3)Ca4Cu square pyramids, and faces with two equivalent O(1)Ca3Cu2 trigonal bipyramids. In the fifth O site, O(5) is bonded in a see-saw-like geometry to one Ca(1), two equivalent Ca(3), and one Cu(1) atom. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Ca(2), two equivalent Ca(3), and one Cu(2) atom. is represented by the CIF card [CIF]
data_Ca3(CuO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.565
_cell_length_b   6.565
_cell_length_c   6.780
_cell_angle_alpha   74.857
_cell_angle_beta   74.857
_cell_angle_gamma   32.786
_symmetry_Int_Tables_number   1
_cell_volume   152.248
_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
  Ca  Ca0  1  0.843  0.843  0.820  1.0
  Ca  Ca1  1  0.842  0.842  0.340  1.0
  Ca  Ca2  1  0.148  0.148  0.173  1.0
  Cu  Cu3  1  0.507  0.507  0.984  1.0
  Cu  Cu4  1  0.513  0.513  0.506  1.0
  O  O5  1  0.987  0.987  0.025  1.0
  O  O6  1  0.991  0.991  0.486  1.0
  O  O7  1  0.357  0.357  0.584  1.0
  O  O8  1  0.346  0.346  0.067  1.0
  O  O9  1  0.655  0.655  0.954  1.0
  O  O10  1  0.661  0.661  0.386  1.0
[/CIF]
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