The crystal structure described by K2CoO3 crystallizes in the orthorhombic Cmce space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to two equivalent O(2), two equivalent O(3), and three equivalent O(1) atoms to form distorted KO7 pentagonal bipyramids that share corners with four equivalent K(1)O7 pentagonal bipyramids,  a cornercorner with one Co(1)O4 tetrahedra, edges with three equivalent K(1)O7 pentagonal bipyramids, and edges with four equivalent Co(1)O4 tetrahedra. In the second K site, K(2) is bonded in a 5-coordinate geometry to two equivalent O(1) and three equivalent O(2) atoms. Co(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form CoO4 tetrahedra that share  a cornercorner with one K(1)O7 pentagonal bipyramid, corners with two equivalent Co(1)O4 tetrahedra, and edges with four equivalent K(1)O7 pentagonal bipyramids. There are three inequivalent O sites. In the first O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1) and two equivalent Co(1) atoms. In the second O site, O(1) is bonded in a 6-coordinate geometry to two equivalent K(2), three equivalent K(1), and one Co(1) atom. In the third O site, O(2) is bonded to two equivalent K(1), three equivalent K(2), and one Co(1) atom to form a mixture of distorted corner and edge-sharing OK5Co octahedra. The corner-sharing octahedral tilt angles are 16°. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2CoO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.449
_cell_length_b   6.449
_cell_length_c   12.807
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   126.084
_symmetry_Int_Tables_number   1
_cell_volume   430.528
_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
  K  K0  1  0.635  0.365  0.424  1.0
  K  K1  1  0.365  0.635  0.576  1.0
  K  K2  1  0.865  0.135  0.924  1.0
  K  K3  1  0.135  0.865  0.076  1.0
  K  K4  1  0.942  0.058  0.360  1.0
  K  K5  1  0.058  0.942  0.640  1.0
  K  K6  1  0.558  0.442  0.860  1.0
  K  K7  1  0.442  0.558  0.140  1.0
  Co  Co8  1  0.757  0.243  0.167  1.0
  Co  Co9  1  0.243  0.757  0.833  1.0
  Co  Co10  1  0.743  0.257  0.667  1.0
  Co  Co11  1  0.257  0.743  0.333  1.0
  O  O12  1  0.665  0.335  0.056  1.0
  O  O13  1  0.335  0.665  0.944  1.0
  O  O14  1  0.835  0.165  0.556  1.0
  O  O15  1  0.165  0.835  0.444  1.0
  O  O16  1  0.906  0.094  0.138  1.0
  O  O17  1  0.094  0.906  0.862  1.0
  O  O18  1  0.594  0.406  0.638  1.0
  O  O19  1  0.406  0.594  0.362  1.0
  O  O20  1  0.967  0.533  0.250  1.0
  O  O21  1  0.033  0.467  0.750  1.0
  O  O22  1  0.533  0.967  0.750  1.0
  O  O23  1  0.467  0.033  0.250  1.0
[/CIF]
.
The crystal structure described by K2CoO3 crystallizes in the orthorhombic Cmce space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to two equivalent O(2), two equivalent O(3), and three equivalent O(1) atoms to form distorted KO7 pentagonal bipyramids that share corners with four equivalent K(1)O7 pentagonal bipyramids,  a cornercorner with one Co(1)O4 tetrahedra, edges with three equivalent K(1)O7 pentagonal bipyramids, and edges with four equivalent Co(1)O4 tetrahedra. In the second K site, K(2) is bonded in a 5-coordinate geometry to two equivalent O(1) and three equivalent O(2) atoms. Co(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form CoO4 tetrahedra that share  a cornercorner with one K(1)O7 pentagonal bipyramid, corners with two equivalent Co(1)O4 tetrahedra, and edges with four equivalent K(1)O7 pentagonal bipyramids. There are three inequivalent O sites. In the first O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1) and two equivalent Co(1) atoms. In the second O site, O(1) is bonded in a 6-coordinate geometry to two equivalent K(2), three equivalent K(1), and one Co(1) atom. In the third O site, O(2) is bonded to two equivalent K(1), three equivalent K(2), and one Co(1) atom to form a mixture of distorted corner and edge-sharing OK5Co octahedra. The corner-sharing octahedral tilt angles are 16°. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2CoO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.449
_cell_length_b   6.449
_cell_length_c   12.807
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   126.084
_symmetry_Int_Tables_number   1
_cell_volume   430.528
_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
  K  K0  1  0.635  0.365  0.424  1.0
  K  K1  1  0.365  0.635  0.576  1.0
  K  K2  1  0.865  0.135  0.924  1.0
  K  K3  1  0.135  0.865  0.076  1.0
  K  K4  1  0.942  0.058  0.360  1.0
  K  K5  1  0.058  0.942  0.640  1.0
  K  K6  1  0.558  0.442  0.860  1.0
  K  K7  1  0.442  0.558  0.140  1.0
  Co  Co8  1  0.757  0.243  0.167  1.0
  Co  Co9  1  0.243  0.757  0.833  1.0
  Co  Co10  1  0.743  0.257  0.667  1.0
  Co  Co11  1  0.257  0.743  0.333  1.0
  O  O12  1  0.665  0.335  0.056  1.0
  O  O13  1  0.335  0.665  0.944  1.0
  O  O14  1  0.835  0.165  0.556  1.0
  O  O15  1  0.165  0.835  0.444  1.0
  O  O16  1  0.906  0.094  0.138  1.0
  O  O17  1  0.094  0.906  0.862  1.0
  O  O18  1  0.594  0.406  0.638  1.0
  O  O19  1  0.406  0.594  0.362  1.0
  O  O20  1  0.967  0.533  0.250  1.0
  O  O21  1  0.033  0.467  0.750  1.0
  O  O22  1  0.533  0.967  0.750  1.0
  O  O23  1  0.467  0.033  0.250  1.0
[/CIF]
.