The compound described by Ca2Co3O8 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted CaO6 octahedra that share corners with six equivalent Co(1)O6 octahedra, corners with three equivalent Ca(2)O4 tetrahedra, and edges with three equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. In the second Ca site, Ca(2) is bonded to one O(4) and three equivalent O(2) atoms to form CaO4 tetrahedra that share corners with three equivalent Ca(1)O6 octahedra and corners with nine equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-76°. Co(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form CoO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with three equivalent Ca(2)O4 tetrahedra,  an edgeedge with one Ca(1)O6 octahedra, and edges with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ca(1) and two equivalent Co(1) atoms. In the second O site, O(2) is bonded to one Ca(1), one Ca(2), and two equivalent Co(1) atoms to form a mixture of corner and edge-sharing OCa2Co2 tetrahedra. In the third O site, O(3) is bonded in a distorted T-shaped geometry to three equivalent Co(1) atoms. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Ca(2) and three equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_Ca2Co3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.996
_cell_length_b   5.996
_cell_length_c   10.513
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   327.279
_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  0.667  0.333  0.025  1.0
  Ca  Ca1  1  0.333  0.667  0.525  1.0
  Ca  Ca2  1  0.667  0.333  0.426  1.0
  Ca  Ca3  1  0.333  0.667  0.926  1.0
  Co  Co4  1  0.672  0.836  0.246  1.0
  Co  Co5  1  0.836  0.164  0.746  1.0
  Co  Co6  1  0.164  0.328  0.246  1.0
  Co  Co7  1  0.836  0.672  0.746  1.0
  Co  Co8  1  0.328  0.164  0.746  1.0
  Co  Co9  1  0.164  0.836  0.246  1.0
  O  O10  1  0.849  0.151  0.161  1.0
  O  O11  1  0.697  0.849  0.661  1.0
  O  O12  1  0.151  0.303  0.661  1.0
  O  O13  1  0.849  0.697  0.161  1.0
  O  O14  1  0.303  0.151  0.161  1.0
  O  O15  1  0.151  0.849  0.661  1.0
  O  O16  1  0.524  0.476  0.842  1.0
  O  O17  1  0.049  0.524  0.342  1.0
  O  O18  1  0.476  0.951  0.342  1.0
  O  O19  1  0.524  0.049  0.842  1.0
  O  O20  1  0.000  0.000  0.359  1.0
  O  O21  1  0.000  0.000  0.859  1.0
  O  O22  1  0.333  0.667  0.134  1.0
  O  O23  1  0.951  0.476  0.842  1.0
  O  O24  1  0.476  0.524  0.342  1.0
  O  O25  1  0.667  0.333  0.634  1.0
[/CIF]
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The compound described by Ca2Co3O8 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted CaO6 octahedra that share corners with six equivalent Co(1)O6 octahedra, corners with three equivalent Ca(2)O4 tetrahedra, and edges with three equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. In the second Ca site, Ca(2) is bonded to one O(4) and three equivalent O(2) atoms to form CaO4 tetrahedra that share corners with three equivalent Ca(1)O6 octahedra and corners with nine equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-76°. Co(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form CoO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with three equivalent Ca(2)O4 tetrahedra,  an edgeedge with one Ca(1)O6 octahedra, and edges with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ca(1) and two equivalent Co(1) atoms. In the second O site, O(2) is bonded to one Ca(1), one Ca(2), and two equivalent Co(1) atoms to form a mixture of corner and edge-sharing OCa2Co2 tetrahedra. In the third O site, O(3) is bonded in a distorted T-shaped geometry to three equivalent Co(1) atoms. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Ca(2) and three equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_Ca2Co3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.996
_cell_length_b   5.996
_cell_length_c   10.513
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   327.279
_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  0.667  0.333  0.025  1.0
  Ca  Ca1  1  0.333  0.667  0.525  1.0
  Ca  Ca2  1  0.667  0.333  0.426  1.0
  Ca  Ca3  1  0.333  0.667  0.926  1.0
  Co  Co4  1  0.672  0.836  0.246  1.0
  Co  Co5  1  0.836  0.164  0.746  1.0
  Co  Co6  1  0.164  0.328  0.246  1.0
  Co  Co7  1  0.836  0.672  0.746  1.0
  Co  Co8  1  0.328  0.164  0.746  1.0
  Co  Co9  1  0.164  0.836  0.246  1.0
  O  O10  1  0.849  0.151  0.161  1.0
  O  O11  1  0.697  0.849  0.661  1.0
  O  O12  1  0.151  0.303  0.661  1.0
  O  O13  1  0.849  0.697  0.161  1.0
  O  O14  1  0.303  0.151  0.161  1.0
  O  O15  1  0.151  0.849  0.661  1.0
  O  O16  1  0.524  0.476  0.842  1.0
  O  O17  1  0.049  0.524  0.342  1.0
  O  O18  1  0.476  0.951  0.342  1.0
  O  O19  1  0.524  0.049  0.842  1.0
  O  O20  1  0.000  0.000  0.359  1.0
  O  O21  1  0.000  0.000  0.859  1.0
  O  O22  1  0.333  0.667  0.134  1.0
  O  O23  1  0.951  0.476  0.842  1.0
  O  O24  1  0.476  0.524  0.342  1.0
  O  O25  1  0.667  0.333  0.634  1.0
[/CIF]
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