The material described by CaCoO2 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(1), two equivalent O(3), and three equivalent O(4) atoms to form distorted CaO6 octahedra that share corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Co(2)O4 trigonal pyramids, edges with three equivalent Ca(2)O6 octahedra, edges with four equivalent Ca(1)O6 octahedra, and  an edgeedge with one Co(2)O4 trigonal pyramid. The corner-sharing octahedral tilt angles are 1°. In the second Ca site, Ca(2) is bonded to one O(3), two equivalent O(4), and three equivalent O(2) atoms to form CaO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Co(2)O4 trigonal pyramids, edges with three equivalent Ca(1)O6 octahedra, edges with four equivalent Ca(2)O6 octahedra, and edges with three equivalent Co(2)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 1°. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded in a distorted square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. In the second Co site, Co(2) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form distorted CoO4 trigonal pyramids that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Co(2)O4 trigonal pyramids,  an edgeedge with one Ca(1)O6 octahedra, and edges with three equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-85°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Co(2), and two equivalent Co(1) atoms to form distorted OCaCo3 tetrahedra that share corners with two equivalent O(4)Ca5Co octahedra, corners with two equivalent O(2)Ca3Co2 square pyramids, corners with four equivalent O(3)Ca3Co2 square pyramids, corners with two equivalent O(1)CaCo3 tetrahedra,  an edgeedge with one O(4)Ca5Co octahedra, and  an edgeedge with one O(3)Ca3Co2 square pyramid. The corner-sharing octahedral tilt angles range from 13-82°. In the second O site, O(2) is bonded to three equivalent Ca(2) and two equivalent Co(2) atoms to form OCa3Co2 square pyramids that share corners with two equivalent O(4)Ca5Co octahedra, corners with three equivalent O(3)Ca3Co2 square pyramids, corners with two equivalent O(1)CaCo3 tetrahedra, edges with three equivalent O(4)Ca5Co octahedra, and edges with four equivalent O(2)Ca3Co2 square pyramids. The corner-sharing octahedral tilt angles are 13°. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and two equivalent Co(1) atoms to form distorted OCa3Co2 square pyramids that share corners with two equivalent O(4)Ca5Co octahedra, corners with three equivalent O(2)Ca3Co2 square pyramids, corners with four equivalent O(1)CaCo3 tetrahedra, edges with three equivalent O(4)Ca5Co octahedra, edges with two equivalent O(3)Ca3Co2 square pyramids, and  an edgeedge with one O(1)CaCo3 tetrahedra. The corner-sharing octahedral tilt angles are 13°. In the fourth O site, O(4) is bonded to two equivalent Ca(2), three equivalent Ca(1), and one Co(2) atom to form OCa5Co octahedra that share corners with two equivalent O(2)Ca3Co2 square pyramids, corners with two equivalent O(3)Ca3Co2 square pyramids, corners with two equivalent O(1)CaCo3 tetrahedra, edges with four equivalent O(4)Ca5Co octahedra, edges with three equivalent O(2)Ca3Co2 square pyramids, edges with three equivalent O(3)Ca3Co2 square pyramids, and  an edgeedge with one O(1)CaCo3 tetrahedra. is represented by the CIF card [CIF]
data_CaCoO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.070
_cell_length_b   8.028
_cell_length_c   8.626
_cell_angle_alpha   85.766
_cell_angle_beta   88.830
_cell_angle_gamma   86.349
_symmetry_Int_Tables_number   1
_cell_volume   211.524
_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  0.769  0.292  0.546  1.0
  Ca  Ca1  1  0.231  0.708  0.454  1.0
  Ca  Ca2  1  0.277  0.416  0.175  1.0
  Ca  Ca3  1  0.723  0.584  0.825  1.0
  Co  Co4  1  0.161  0.942  0.700  1.0
  Co  Co5  1  0.308  0.249  0.871  1.0
  Co  Co6  1  0.692  0.751  0.129  1.0
  Co  Co7  1  0.839  0.058  0.300  1.0
  O  O8  1  0.383  0.917  0.254  1.0
  O  O9  1  0.199  0.675  0.005  1.0
  O  O10  1  0.801  0.325  0.995  1.0
  O  O11  1  0.617  0.083  0.746  1.0
  O  O12  1  0.702  0.805  0.635  1.0
  O  O13  1  0.245  0.436  0.682  1.0
  O  O14  1  0.298  0.195  0.365  1.0
  O  O15  1  0.755  0.564  0.318  1.0
[/CIF]
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The material described by CaCoO2 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(1), two equivalent O(3), and three equivalent O(4) atoms to form distorted CaO6 octahedra that share corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Co(2)O4 trigonal pyramids, edges with three equivalent Ca(2)O6 octahedra, edges with four equivalent Ca(1)O6 octahedra, and  an edgeedge with one Co(2)O4 trigonal pyramid. The corner-sharing octahedral tilt angles are 1°. In the second Ca site, Ca(2) is bonded to one O(3), two equivalent O(4), and three equivalent O(2) atoms to form CaO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Co(2)O4 trigonal pyramids, edges with three equivalent Ca(1)O6 octahedra, edges with four equivalent Ca(2)O6 octahedra, and edges with three equivalent Co(2)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 1°. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded in a distorted square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. In the second Co site, Co(2) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form distorted CoO4 trigonal pyramids that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Co(2)O4 trigonal pyramids,  an edgeedge with one Ca(1)O6 octahedra, and edges with three equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-85°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Co(2), and two equivalent Co(1) atoms to form distorted OCaCo3 tetrahedra that share corners with two equivalent O(4)Ca5Co octahedra, corners with two equivalent O(2)Ca3Co2 square pyramids, corners with four equivalent O(3)Ca3Co2 square pyramids, corners with two equivalent O(1)CaCo3 tetrahedra,  an edgeedge with one O(4)Ca5Co octahedra, and  an edgeedge with one O(3)Ca3Co2 square pyramid. The corner-sharing octahedral tilt angles range from 13-82°. In the second O site, O(2) is bonded to three equivalent Ca(2) and two equivalent Co(2) atoms to form OCa3Co2 square pyramids that share corners with two equivalent O(4)Ca5Co octahedra, corners with three equivalent O(3)Ca3Co2 square pyramids, corners with two equivalent O(1)CaCo3 tetrahedra, edges with three equivalent O(4)Ca5Co octahedra, and edges with four equivalent O(2)Ca3Co2 square pyramids. The corner-sharing octahedral tilt angles are 13°. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and two equivalent Co(1) atoms to form distorted OCa3Co2 square pyramids that share corners with two equivalent O(4)Ca5Co octahedra, corners with three equivalent O(2)Ca3Co2 square pyramids, corners with four equivalent O(1)CaCo3 tetrahedra, edges with three equivalent O(4)Ca5Co octahedra, edges with two equivalent O(3)Ca3Co2 square pyramids, and  an edgeedge with one O(1)CaCo3 tetrahedra. The corner-sharing octahedral tilt angles are 13°. In the fourth O site, O(4) is bonded to two equivalent Ca(2), three equivalent Ca(1), and one Co(2) atom to form OCa5Co octahedra that share corners with two equivalent O(2)Ca3Co2 square pyramids, corners with two equivalent O(3)Ca3Co2 square pyramids, corners with two equivalent O(1)CaCo3 tetrahedra, edges with four equivalent O(4)Ca5Co octahedra, edges with three equivalent O(2)Ca3Co2 square pyramids, edges with three equivalent O(3)Ca3Co2 square pyramids, and  an edgeedge with one O(1)CaCo3 tetrahedra. is represented by the CIF card [CIF]
data_CaCoO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.070
_cell_length_b   8.028
_cell_length_c   8.626
_cell_angle_alpha   85.766
_cell_angle_beta   88.830
_cell_angle_gamma   86.349
_symmetry_Int_Tables_number   1
_cell_volume   211.524
_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  0.769  0.292  0.546  1.0
  Ca  Ca1  1  0.231  0.708  0.454  1.0
  Ca  Ca2  1  0.277  0.416  0.175  1.0
  Ca  Ca3  1  0.723  0.584  0.825  1.0
  Co  Co4  1  0.161  0.942  0.700  1.0
  Co  Co5  1  0.308  0.249  0.871  1.0
  Co  Co6  1  0.692  0.751  0.129  1.0
  Co  Co7  1  0.839  0.058  0.300  1.0
  O  O8  1  0.383  0.917  0.254  1.0
  O  O9  1  0.199  0.675  0.005  1.0
  O  O10  1  0.801  0.325  0.995  1.0
  O  O11  1  0.617  0.083  0.746  1.0
  O  O12  1  0.702  0.805  0.635  1.0
  O  O13  1  0.245  0.436  0.682  1.0
  O  O14  1  0.298  0.195  0.365  1.0
  O  O15  1  0.755  0.564  0.318  1.0
[/CIF]
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