The material described by CaCo2O4 crystallizes in the monoclinic C2/m space group. Ca(1) is bonded in a 7-coordinate geometry to one O(2), two equivalent O(4), and four equivalent O(3) atoms. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form CoO5 square pyramids that share corners with four equivalent Co(2)O6 octahedra and edges with two equivalent Co(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 52-54°. In the second Co site, Co(2) is bonded to one O(1), two equivalent O(2), and three equivalent O(4) atoms to form CoO6 octahedra that share corners with four equivalent Co(1)O5 square pyramids and edges with four equivalent Co(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Co(2) and two equivalent Co(1) atoms. In the second O site, O(2) is bonded to one Ca(1), one Co(1), and two equivalent Co(2) atoms to form distorted OCaCo3 trigonal pyramids that share corners with two equivalent O(4)Ca2Co3 square pyramids, corners with two equivalent O(2)CaCo3 trigonal pyramids, and edges with three equivalent O(4)Ca2Co3 square pyramids. In the third O site, O(3) is bonded in a 6-coordinate geometry to four equivalent Ca(1) and two equivalent Co(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Ca(1) and three equivalent Co(2) atoms to form OCa2Co3 square pyramids that share corners with two equivalent O(2)CaCo3 trigonal pyramids, edges with four equivalent O(4)Ca2Co3 square pyramids, and edges with three equivalent O(2)CaCo3 trigonal pyramids. is represented by the CIF card [CIF]
data_Ca(CoO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.127
_cell_length_b   7.127
_cell_length_c   8.748
_cell_angle_alpha   61.584
_cell_angle_beta   61.584
_cell_angle_gamma   23.610
_symmetry_Int_Tables_number   1
_cell_volume   155.525
_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  0.614  0.614  0.846  1.0
  Ca  Ca1  1  0.386  0.386  0.154  1.0
  Co  Co2  1  0.423  0.423  0.766  1.0
  Co  Co3  1  0.835  0.835  0.516  1.0
  Co  Co4  1  0.165  0.165  0.484  1.0
  Co  Co5  1  0.577  0.577  0.234  1.0
  O  O6  1  0.122  0.122  0.307  1.0
  O  O7  1  0.573  0.573  0.618  1.0
  O  O8  1  0.427  0.427  0.382  1.0
  O  O9  1  0.878  0.878  0.693  1.0
  O  O10  1  0.940  0.940  0.909  1.0
  O  O11  1  0.231  0.231  0.637  1.0
  O  O12  1  0.060  0.060  0.091  1.0
  O  O13  1  0.769  0.769  0.363  1.0
[/CIF]
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The material described by CaCo2O4 crystallizes in the monoclinic C2/m space group. Ca(1) is bonded in a 7-coordinate geometry to one O(2), two equivalent O(4), and four equivalent O(3) atoms. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form CoO5 square pyramids that share corners with four equivalent Co(2)O6 octahedra and edges with two equivalent Co(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 52-54°. In the second Co site, Co(2) is bonded to one O(1), two equivalent O(2), and three equivalent O(4) atoms to form CoO6 octahedra that share corners with four equivalent Co(1)O5 square pyramids and edges with four equivalent Co(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Co(2) and two equivalent Co(1) atoms. In the second O site, O(2) is bonded to one Ca(1), one Co(1), and two equivalent Co(2) atoms to form distorted OCaCo3 trigonal pyramids that share corners with two equivalent O(4)Ca2Co3 square pyramids, corners with two equivalent O(2)CaCo3 trigonal pyramids, and edges with three equivalent O(4)Ca2Co3 square pyramids. In the third O site, O(3) is bonded in a 6-coordinate geometry to four equivalent Ca(1) and two equivalent Co(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Ca(1) and three equivalent Co(2) atoms to form OCa2Co3 square pyramids that share corners with two equivalent O(2)CaCo3 trigonal pyramids, edges with four equivalent O(4)Ca2Co3 square pyramids, and edges with three equivalent O(2)CaCo3 trigonal pyramids. is represented by the CIF card [CIF]
data_Ca(CoO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.127
_cell_length_b   7.127
_cell_length_c   8.748
_cell_angle_alpha   61.584
_cell_angle_beta   61.584
_cell_angle_gamma   23.610
_symmetry_Int_Tables_number   1
_cell_volume   155.525
_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  0.614  0.614  0.846  1.0
  Ca  Ca1  1  0.386  0.386  0.154  1.0
  Co  Co2  1  0.423  0.423  0.766  1.0
  Co  Co3  1  0.835  0.835  0.516  1.0
  Co  Co4  1  0.165  0.165  0.484  1.0
  Co  Co5  1  0.577  0.577  0.234  1.0
  O  O6  1  0.122  0.122  0.307  1.0
  O  O7  1  0.573  0.573  0.618  1.0
  O  O8  1  0.427  0.427  0.382  1.0
  O  O9  1  0.878  0.878  0.693  1.0
  O  O10  1  0.940  0.940  0.909  1.0
  O  O11  1  0.231  0.231  0.637  1.0
  O  O12  1  0.060  0.060  0.091  1.0
  O  O13  1  0.769  0.769  0.363  1.0
[/CIF]
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