The structure described by CaCoO2 crystallizes in the triclinic P1 space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(6), one O(7), two equivalent O(2), and two equivalent O(4) atoms to form distorted CaO6 octahedra that share  a cornercorner with one Co(3)O4 tetrahedra, edges with two equivalent Ca(1)O6 octahedra, and edges with two equivalent Co(2)O5 square pyramids. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to one O(7), one O(8), two equivalent O(1), and two equivalent O(5) atoms. In the third Ca site, Ca(3) is bonded in a 6-coordinate geometry to one O(7), one O(8), two equivalent O(2), and two equivalent O(5) atoms. In the fourth Ca site, Ca(4) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(3) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a 4-coordinate geometry to two equivalent O(4) and two equivalent O(5) atoms. In the second Co site, Co(2) is bonded to one O(4), two equivalent O(3), and two equivalent O(6) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Co(3)O4 tetrahedra, edges with two equivalent Ca(1)O6 octahedra, and edges with two equivalent Co(2)O5 square pyramids. In the third Co site, Co(3) is bonded to one O(1), one O(6), and two equivalent O(8) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(1)O6 octahedra, corners with two equivalent Co(2)O5 square pyramids, and corners with two equivalent Co(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the fourth Co site, Co(4) is bonded in a trigonal planar geometry to one O(3) and two equivalent O(7) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(2), two equivalent Ca(4), and one Co(3) atom to form OCa4Co trigonal bipyramids that share  a cornercorner with one O(6)CaCo3 tetrahedra, corners with two equivalent O(3)Ca2Co3 trigonal bipyramids, corners with two equivalent O(2)Ca5 trigonal bipyramids,  an edgeedge with one O(3)Ca2Co3 trigonal bipyramid, edges with two equivalent O(1)Ca4Co trigonal bipyramids, and edges with two equivalent O(8)Ca2Co2 trigonal pyramids. In the second O site, O(2) is bonded to one Ca(4), two equivalent Ca(1), and two equivalent Ca(3) atoms to form distorted OCa5 trigonal bipyramids that share corners with two equivalent O(4)Ca2Co3 square pyramids, corners with two equivalent O(6)CaCo3 tetrahedra, corners with two equivalent O(3)Ca2Co3 trigonal bipyramids, corners with two equivalent O(1)Ca4Co trigonal bipyramids, corners with two equivalent O(8)Ca2Co2 trigonal pyramids,  an edgeedge with one O(4)Ca2Co3 square pyramid, and edges with two equivalent O(2)Ca5 trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Ca(4), one Co(4), and two equivalent Co(2) atoms to form distorted OCa2Co3 trigonal bipyramids that share corners with two equivalent O(4)Ca2Co3 square pyramids, corners with two equivalent O(6)CaCo3 tetrahedra, corners with two equivalent O(1)Ca4Co trigonal bipyramids, corners with two equivalent O(2)Ca5 trigonal bipyramids,  an edgeedge with one O(6)CaCo3 tetrahedra,  an edgeedge with one O(1)Ca4Co trigonal bipyramid, and edges with two equivalent O(3)Ca2Co3 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Ca(1), one Co(2), and two equivalent Co(1) atoms to form distorted OCa2Co3 square pyramids that share corners with two equivalent O(3)Ca2Co3 trigonal bipyramids, corners with two equivalent O(2)Ca5 trigonal bipyramids, edges with two equivalent O(4)Ca2Co3 square pyramids, edges with two equivalent O(6)CaCo3 tetrahedra, and  an edgeedge with one O(2)Ca5 trigonal bipyramid. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to two equivalent Ca(2), two equivalent Ca(3), and two equivalent Co(1) atoms. In the sixth O site, O(6) is bonded to one Ca(1), one Co(3), and two equivalent Co(2) atoms to form OCaCo3 tetrahedra that share corners with two equivalent O(6)CaCo3 tetrahedra,  a cornercorner with one O(1)Ca4Co trigonal bipyramid, corners with two equivalent O(3)Ca2Co3 trigonal bipyramids, corners with two equivalent O(2)Ca5 trigonal bipyramids, corners with two equivalent O(8)Ca2Co2 trigonal pyramids, edges with two equivalent O(4)Ca2Co3 square pyramids, and  an edgeedge with one O(3)Ca2Co3 trigonal bipyramid. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Ca(1), one Ca(2), one Ca(3), and two equivalent Co(4) atoms. In the eighth O site, O(8) is bonded to one Ca(2), one Ca(3), and two equivalent Co(3) atoms to form OCa2Co2 trigonal pyramids that share corners with two equivalent O(6)CaCo3 tetrahedra, corners with two equivalent O(2)Ca5 trigonal bipyramids, corners with two equivalent O(8)Ca2Co2 trigonal pyramids, and edges with two equivalent O(1)Ca4Co trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaCoO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.101
_cell_length_b   8.332
_cell_length_c   9.074
_cell_angle_alpha   111.055
_cell_angle_beta   99.373
_cell_angle_gamma   91.675
_symmetry_Int_Tables_number   1
_cell_volume   214.899
_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  0.938  0.827  0.183  1.0
  Ca  Ca1  1  0.742  0.351  0.798  1.0
  Ca  Ca2  1  0.877  0.079  0.004  1.0
  Ca  Ca3  1  0.547  0.300  0.418  1.0
  Co  Co4  1  0.884  0.462  0.123  1.0
  Co  Co5  1  0.550  0.689  0.446  1.0
  Co  Co6  1  0.123  0.035  0.618  1.0
  Co  Co7  1  0.208  0.669  0.721  1.0
  O  O8  1  0.136  0.270  0.596  1.0
  O  O9  1  0.461  0.039  0.182  1.0
  O  O10  1  0.064  0.548  0.489  1.0
  O  O11  1  0.421  0.612  0.193  1.0
  O  O12  1  0.347  0.314  0.018  1.0
  O  O13  1  0.053  0.832  0.435  1.0
  O  O14  1  0.769  0.689  0.859  1.0
  O  O15  1  0.689  0.058  0.755  1.0
[/CIF]
.
The structure described by CaCoO2 crystallizes in the triclinic P1 space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(6), one O(7), two equivalent O(2), and two equivalent O(4) atoms to form distorted CaO6 octahedra that share  a cornercorner with one Co(3)O4 tetrahedra, edges with two equivalent Ca(1)O6 octahedra, and edges with two equivalent Co(2)O5 square pyramids. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to one O(7), one O(8), two equivalent O(1), and two equivalent O(5) atoms. In the third Ca site, Ca(3) is bonded in a 6-coordinate geometry to one O(7), one O(8), two equivalent O(2), and two equivalent O(5) atoms. In the fourth Ca site, Ca(4) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(3) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a 4-coordinate geometry to two equivalent O(4) and two equivalent O(5) atoms. In the second Co site, Co(2) is bonded to one O(4), two equivalent O(3), and two equivalent O(6) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Co(3)O4 tetrahedra, edges with two equivalent Ca(1)O6 octahedra, and edges with two equivalent Co(2)O5 square pyramids. In the third Co site, Co(3) is bonded to one O(1), one O(6), and two equivalent O(8) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(1)O6 octahedra, corners with two equivalent Co(2)O5 square pyramids, and corners with two equivalent Co(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the fourth Co site, Co(4) is bonded in a trigonal planar geometry to one O(3) and two equivalent O(7) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(2), two equivalent Ca(4), and one Co(3) atom to form OCa4Co trigonal bipyramids that share  a cornercorner with one O(6)CaCo3 tetrahedra, corners with two equivalent O(3)Ca2Co3 trigonal bipyramids, corners with two equivalent O(2)Ca5 trigonal bipyramids,  an edgeedge with one O(3)Ca2Co3 trigonal bipyramid, edges with two equivalent O(1)Ca4Co trigonal bipyramids, and edges with two equivalent O(8)Ca2Co2 trigonal pyramids. In the second O site, O(2) is bonded to one Ca(4), two equivalent Ca(1), and two equivalent Ca(3) atoms to form distorted OCa5 trigonal bipyramids that share corners with two equivalent O(4)Ca2Co3 square pyramids, corners with two equivalent O(6)CaCo3 tetrahedra, corners with two equivalent O(3)Ca2Co3 trigonal bipyramids, corners with two equivalent O(1)Ca4Co trigonal bipyramids, corners with two equivalent O(8)Ca2Co2 trigonal pyramids,  an edgeedge with one O(4)Ca2Co3 square pyramid, and edges with two equivalent O(2)Ca5 trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Ca(4), one Co(4), and two equivalent Co(2) atoms to form distorted OCa2Co3 trigonal bipyramids that share corners with two equivalent O(4)Ca2Co3 square pyramids, corners with two equivalent O(6)CaCo3 tetrahedra, corners with two equivalent O(1)Ca4Co trigonal bipyramids, corners with two equivalent O(2)Ca5 trigonal bipyramids,  an edgeedge with one O(6)CaCo3 tetrahedra,  an edgeedge with one O(1)Ca4Co trigonal bipyramid, and edges with two equivalent O(3)Ca2Co3 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Ca(1), one Co(2), and two equivalent Co(1) atoms to form distorted OCa2Co3 square pyramids that share corners with two equivalent O(3)Ca2Co3 trigonal bipyramids, corners with two equivalent O(2)Ca5 trigonal bipyramids, edges with two equivalent O(4)Ca2Co3 square pyramids, edges with two equivalent O(6)CaCo3 tetrahedra, and  an edgeedge with one O(2)Ca5 trigonal bipyramid. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to two equivalent Ca(2), two equivalent Ca(3), and two equivalent Co(1) atoms. In the sixth O site, O(6) is bonded to one Ca(1), one Co(3), and two equivalent Co(2) atoms to form OCaCo3 tetrahedra that share corners with two equivalent O(6)CaCo3 tetrahedra,  a cornercorner with one O(1)Ca4Co trigonal bipyramid, corners with two equivalent O(3)Ca2Co3 trigonal bipyramids, corners with two equivalent O(2)Ca5 trigonal bipyramids, corners with two equivalent O(8)Ca2Co2 trigonal pyramids, edges with two equivalent O(4)Ca2Co3 square pyramids, and  an edgeedge with one O(3)Ca2Co3 trigonal bipyramid. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Ca(1), one Ca(2), one Ca(3), and two equivalent Co(4) atoms. In the eighth O site, O(8) is bonded to one Ca(2), one Ca(3), and two equivalent Co(3) atoms to form OCa2Co2 trigonal pyramids that share corners with two equivalent O(6)CaCo3 tetrahedra, corners with two equivalent O(2)Ca5 trigonal bipyramids, corners with two equivalent O(8)Ca2Co2 trigonal pyramids, and edges with two equivalent O(1)Ca4Co trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaCoO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.101
_cell_length_b   8.332
_cell_length_c   9.074
_cell_angle_alpha   111.055
_cell_angle_beta   99.373
_cell_angle_gamma   91.675
_symmetry_Int_Tables_number   1
_cell_volume   214.899
_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  0.938  0.827  0.183  1.0
  Ca  Ca1  1  0.742  0.351  0.798  1.0
  Ca  Ca2  1  0.877  0.079  0.004  1.0
  Ca  Ca3  1  0.547  0.300  0.418  1.0
  Co  Co4  1  0.884  0.462  0.123  1.0
  Co  Co5  1  0.550  0.689  0.446  1.0
  Co  Co6  1  0.123  0.035  0.618  1.0
  Co  Co7  1  0.208  0.669  0.721  1.0
  O  O8  1  0.136  0.270  0.596  1.0
  O  O9  1  0.461  0.039  0.182  1.0
  O  O10  1  0.064  0.548  0.489  1.0
  O  O11  1  0.421  0.612  0.193  1.0
  O  O12  1  0.347  0.314  0.018  1.0
  O  O13  1  0.053  0.832  0.435  1.0
  O  O14  1  0.769  0.689  0.859  1.0
  O  O15  1  0.689  0.058  0.755  1.0
[/CIF]
.