The structure described by Na2CoO3 crystallizes in the monoclinic Pm space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(2), one O(7), one O(8), and two equivalent O(5) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(1)O4 tetrahedra,  a cornercorner with one Co(4)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Na(2)O5 trigonal bipyramids, corners with three equivalent Na(1)O5 trigonal bipyramids,  an edgeedge with one Co(1)O4 tetrahedra, edges with two equivalent Na(3)O5 trigonal bipyramids, and edges with two equivalent Na(4)O5 trigonal bipyramids. In the second Na site, Na(2) is bonded to one O(1), one O(7), one O(8), and two equivalent O(6) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(3)O4 tetrahedra, corners with two equivalent Co(4)O4 tetrahedra, corners with two equivalent Na(1)O5 trigonal bipyramids, corners with three equivalent Na(2)O5 trigonal bipyramids,  an edgeedge with one Co(3)O4 tetrahedra, edges with two equivalent Na(3)O5 trigonal bipyramids, and edges with two equivalent Na(4)O5 trigonal bipyramids. In the third Na site, Na(3) is bonded to one O(4), one O(5), one O(6), and two equivalent O(7) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(3)O4 tetrahedra, corners with two equivalent Co(1)O4 tetrahedra, corners with two equivalent Na(4)O5 trigonal bipyramids, corners with three equivalent Na(3)O5 trigonal bipyramids,  an edgeedge with one Co(2)O4 tetrahedra, edges with two equivalent Na(1)O5 trigonal bipyramids, and edges with two equivalent Na(2)O5 trigonal bipyramids. In the fourth Na site, Na(4) is bonded to one O(3), one O(5), one O(6), and two equivalent O(8) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(1)O4 tetrahedra,  a cornercorner with one Co(4)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra, corners with two equivalent Na(3)O5 trigonal bipyramids, corners with three equivalent Na(4)O5 trigonal bipyramids,  an edgeedge with one Co(4)O4 tetrahedra, edges with two equivalent Na(1)O5 trigonal bipyramids, and edges with two equivalent Na(2)O5 trigonal bipyramids. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(4), and two equivalent O(5) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Na(1)O5 trigonal bipyramids, corners with two equivalent Na(4)O5 trigonal bipyramids, corners with four equivalent Na(3)O5 trigonal bipyramids, and edges with two equivalent Na(1)O5 trigonal bipyramids. In the second Co site, Co(2) is bonded to one O(2), one O(4), and two equivalent O(7) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(1)O4 tetrahedra, corners with two equivalent Na(2)O5 trigonal bipyramids, corners with two equivalent Na(3)O5 trigonal bipyramids, corners with four equivalent Na(1)O5 trigonal bipyramids, and edges with two equivalent Na(3)O5 trigonal bipyramids. In the third Co site, Co(3) is bonded to one O(1), one O(3), and two equivalent O(6) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(4)O4 tetrahedra, corners with two equivalent Na(2)O5 trigonal bipyramids, corners with two equivalent Na(3)O5 trigonal bipyramids, corners with four equivalent Na(4)O5 trigonal bipyramids, and edges with two equivalent Na(2)O5 trigonal bipyramids. In the fourth Co site, Co(4) is bonded to one O(1), one O(3), and two equivalent O(8) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(3)O4 tetrahedra, corners with two equivalent Na(1)O5 trigonal bipyramids, corners with two equivalent Na(4)O5 trigonal bipyramids, corners with four equivalent Na(2)O5 trigonal bipyramids, and edges with two equivalent Na(4)O5 trigonal bipyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(2), one Co(3), and one Co(4) atom to form ONa2Co2 tetrahedra that share corners with two equivalent O(3)Na2Co2 tetrahedra, corners with two equivalent O(6)Na4Co trigonal bipyramids, corners with two equivalent O(7)Na4Co trigonal bipyramids, corners with four equivalent O(8)Na4Co trigonal bipyramids, and edges with two equivalent O(6)Na4Co trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Na(1), one Co(1), and one Co(2) atom to form ONa2Co2 tetrahedra that share corners with two equivalent O(4)Na2Co2 tetrahedra, corners with two equivalent O(5)Na4Co trigonal bipyramids, corners with two equivalent O(8)Na4Co trigonal bipyramids, corners with four equivalent O(7)Na4Co trigonal bipyramids, and edges with two equivalent O(5)Na4Co trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Na(4), one Co(3), and one Co(4) atom to form ONa2Co2 tetrahedra that share corners with two equivalent O(1)Na2Co2 tetrahedra, corners with two equivalent O(5)Na4Co trigonal bipyramids, corners with two equivalent O(8)Na4Co trigonal bipyramids, corners with four equivalent O(6)Na4Co trigonal bipyramids, and edges with two equivalent O(8)Na4Co trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Na(3), one Co(1), and one Co(2) atom to form distorted ONa2Co2 tetrahedra that share corners with two equivalent O(2)Na2Co2 tetrahedra, corners with two equivalent O(6)Na4Co trigonal bipyramids, corners with two equivalent O(7)Na4Co trigonal bipyramids, corners with four equivalent O(5)Na4Co trigonal bipyramids, and edges with two equivalent O(7)Na4Co trigonal bipyramids. In the fifth O site, O(5) is bonded to one Na(3), one Na(4), two equivalent Na(1), and one Co(1) atom to form distorted ONa4Co trigonal bipyramids that share  a cornercorner with one O(2)Na2Co2 tetrahedra,  a cornercorner with one O(3)Na2Co2 tetrahedra, corners with two equivalent O(4)Na2Co2 tetrahedra, corners with two equivalent O(6)Na4Co trigonal bipyramids, corners with three equivalent O(5)Na4Co trigonal bipyramids,  an edgeedge with one O(2)Na2Co2 tetrahedra, edges with two equivalent O(7)Na4Co trigonal bipyramids, and edges with two equivalent O(8)Na4Co trigonal bipyramids. In the sixth O site, O(6) is bonded to one Na(3), one Na(4), two equivalent Na(2), and one Co(3) atom to form distorted ONa4Co trigonal bipyramids that share  a cornercorner with one O(1)Na2Co2 tetrahedra,  a cornercorner with one O(4)Na2Co2 tetrahedra, corners with two equivalent O(3)Na2Co2 tetrahedra, corners with two equivalent O(5)Na4Co trigonal bipyramids, corners with three equivalent O(6)Na4Co trigonal bipyramids,  an edgeedge with one O(1)Na2Co2 tetrahedra, edges with two equivalent O(7)Na4Co trigonal bipyramids, and edges with two equivalent O(8)Na4Co trigonal bipyramids. In the seventh O site, O(7) is bonded to one Na(1), one Na(2), two equivalent Na(3), and one Co(2) atom to form distorted ONa4Co trigonal bipyramids that share  a cornercorner with one O(1)Na2Co2 tetrahedra,  a cornercorner with one O(4)Na2Co2 tetrahedra, corners with two equivalent O(2)Na2Co2 tetrahedra, corners with two equivalent O(8)Na4Co trigonal bipyramids, corners with three equivalent O(7)Na4Co trigonal bipyramids,  an edgeedge with one O(4)Na2Co2 tetrahedra, edges with two equivalent O(5)Na4Co trigonal bipyramids, and edges with two equivalent O(6)Na4Co trigonal bipyramids. In the eighth O site, O(8) is bonded to one Na(1), one Na(2), two equivalent Na(4), and one Co(4) atom to form distorted ONa4Co trigonal bipyramids that share  a cornercorner with one O(2)Na2Co2 tetrahedra,  a cornercorner with one O(3)Na2Co2 tetrahedra, corners with two equivalent O(1)Na2Co2 tetrahedra, corners with two equivalent O(7)Na4Co trigonal bipyramids, corners with three equivalent O(8)Na4Co trigonal bipyramids,  an edgeedge with one O(3)Na2Co2 tetrahedra, edges with two equivalent O(5)Na4Co trigonal bipyramids, and edges with two equivalent O(6)Na4Co trigonal bipyramids. is represented by the CIF card [CIF]
data_Na2CoO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.063
_cell_length_b   6.020
_cell_length_c   11.283
_cell_angle_alpha   89.999
_cell_angle_beta   90.000
_cell_angle_gamma   90.419
_symmetry_Int_Tables_number   1
_cell_volume   343.890
_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
  Na  Na0  1  0.513  0.186  0.335  1.0
  Na  Na1  1  0.513  0.679  0.836  1.0
  Na  Na2  1  0.015  0.819  0.339  1.0
  Na  Na3  1  0.018  0.320  0.839  1.0
  Na  Na4  1  0.513  0.679  0.164  1.0
  Na  Na5  1  0.513  0.186  0.665  1.0
  Na  Na6  1  0.018  0.320  0.161  1.0
  Na  Na7  1  0.015  0.819  0.661  1.0
  Co  Co8  1  0.041  0.319  0.500  1.0
  Co  Co9  1  0.543  0.682  0.500  1.0
  Co  Co10  1  0.038  0.814  0.000  1.0
  Co  Co11  1  0.549  0.159  0.000  1.0
  O  O12  1  0.407  0.880  0.000  1.0
  O  O13  1  0.392  0.396  0.500  1.0
  O  O14  1  0.907  0.107  1.000  1.0
  O  O15  1  0.892  0.603  0.500  1.0
  O  O16  1  0.995  0.211  0.359  1.0
  O  O17  1  0.994  0.715  0.858  1.0
  O  O18  1  0.497  0.792  0.360  1.0
  O  O19  1  0.487  0.300  0.865  1.0
  O  O20  1  0.994  0.715  0.142  1.0
  O  O21  1  0.995  0.211  0.641  1.0
  O  O22  1  0.487  0.300  0.135  1.0
  O  O23  1  0.497  0.792  0.640  1.0
[/CIF]
.
The structure described by Na2CoO3 crystallizes in the monoclinic Pm space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(2), one O(7), one O(8), and two equivalent O(5) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(1)O4 tetrahedra,  a cornercorner with one Co(4)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Na(2)O5 trigonal bipyramids, corners with three equivalent Na(1)O5 trigonal bipyramids,  an edgeedge with one Co(1)O4 tetrahedra, edges with two equivalent Na(3)O5 trigonal bipyramids, and edges with two equivalent Na(4)O5 trigonal bipyramids. In the second Na site, Na(2) is bonded to one O(1), one O(7), one O(8), and two equivalent O(6) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(3)O4 tetrahedra, corners with two equivalent Co(4)O4 tetrahedra, corners with two equivalent Na(1)O5 trigonal bipyramids, corners with three equivalent Na(2)O5 trigonal bipyramids,  an edgeedge with one Co(3)O4 tetrahedra, edges with two equivalent Na(3)O5 trigonal bipyramids, and edges with two equivalent Na(4)O5 trigonal bipyramids. In the third Na site, Na(3) is bonded to one O(4), one O(5), one O(6), and two equivalent O(7) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(3)O4 tetrahedra, corners with two equivalent Co(1)O4 tetrahedra, corners with two equivalent Na(4)O5 trigonal bipyramids, corners with three equivalent Na(3)O5 trigonal bipyramids,  an edgeedge with one Co(2)O4 tetrahedra, edges with two equivalent Na(1)O5 trigonal bipyramids, and edges with two equivalent Na(2)O5 trigonal bipyramids. In the fourth Na site, Na(4) is bonded to one O(3), one O(5), one O(6), and two equivalent O(8) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(1)O4 tetrahedra,  a cornercorner with one Co(4)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra, corners with two equivalent Na(3)O5 trigonal bipyramids, corners with three equivalent Na(4)O5 trigonal bipyramids,  an edgeedge with one Co(4)O4 tetrahedra, edges with two equivalent Na(1)O5 trigonal bipyramids, and edges with two equivalent Na(2)O5 trigonal bipyramids. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(4), and two equivalent O(5) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Na(1)O5 trigonal bipyramids, corners with two equivalent Na(4)O5 trigonal bipyramids, corners with four equivalent Na(3)O5 trigonal bipyramids, and edges with two equivalent Na(1)O5 trigonal bipyramids. In the second Co site, Co(2) is bonded to one O(2), one O(4), and two equivalent O(7) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(1)O4 tetrahedra, corners with two equivalent Na(2)O5 trigonal bipyramids, corners with two equivalent Na(3)O5 trigonal bipyramids, corners with four equivalent Na(1)O5 trigonal bipyramids, and edges with two equivalent Na(3)O5 trigonal bipyramids. In the third Co site, Co(3) is bonded to one O(1), one O(3), and two equivalent O(6) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(4)O4 tetrahedra, corners with two equivalent Na(2)O5 trigonal bipyramids, corners with two equivalent Na(3)O5 trigonal bipyramids, corners with four equivalent Na(4)O5 trigonal bipyramids, and edges with two equivalent Na(2)O5 trigonal bipyramids. In the fourth Co site, Co(4) is bonded to one O(1), one O(3), and two equivalent O(8) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(3)O4 tetrahedra, corners with two equivalent Na(1)O5 trigonal bipyramids, corners with two equivalent Na(4)O5 trigonal bipyramids, corners with four equivalent Na(2)O5 trigonal bipyramids, and edges with two equivalent Na(4)O5 trigonal bipyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(2), one Co(3), and one Co(4) atom to form ONa2Co2 tetrahedra that share corners with two equivalent O(3)Na2Co2 tetrahedra, corners with two equivalent O(6)Na4Co trigonal bipyramids, corners with two equivalent O(7)Na4Co trigonal bipyramids, corners with four equivalent O(8)Na4Co trigonal bipyramids, and edges with two equivalent O(6)Na4Co trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Na(1), one Co(1), and one Co(2) atom to form ONa2Co2 tetrahedra that share corners with two equivalent O(4)Na2Co2 tetrahedra, corners with two equivalent O(5)Na4Co trigonal bipyramids, corners with two equivalent O(8)Na4Co trigonal bipyramids, corners with four equivalent O(7)Na4Co trigonal bipyramids, and edges with two equivalent O(5)Na4Co trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Na(4), one Co(3), and one Co(4) atom to form ONa2Co2 tetrahedra that share corners with two equivalent O(1)Na2Co2 tetrahedra, corners with two equivalent O(5)Na4Co trigonal bipyramids, corners with two equivalent O(8)Na4Co trigonal bipyramids, corners with four equivalent O(6)Na4Co trigonal bipyramids, and edges with two equivalent O(8)Na4Co trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Na(3), one Co(1), and one Co(2) atom to form distorted ONa2Co2 tetrahedra that share corners with two equivalent O(2)Na2Co2 tetrahedra, corners with two equivalent O(6)Na4Co trigonal bipyramids, corners with two equivalent O(7)Na4Co trigonal bipyramids, corners with four equivalent O(5)Na4Co trigonal bipyramids, and edges with two equivalent O(7)Na4Co trigonal bipyramids. In the fifth O site, O(5) is bonded to one Na(3), one Na(4), two equivalent Na(1), and one Co(1) atom to form distorted ONa4Co trigonal bipyramids that share  a cornercorner with one O(2)Na2Co2 tetrahedra,  a cornercorner with one O(3)Na2Co2 tetrahedra, corners with two equivalent O(4)Na2Co2 tetrahedra, corners with two equivalent O(6)Na4Co trigonal bipyramids, corners with three equivalent O(5)Na4Co trigonal bipyramids,  an edgeedge with one O(2)Na2Co2 tetrahedra, edges with two equivalent O(7)Na4Co trigonal bipyramids, and edges with two equivalent O(8)Na4Co trigonal bipyramids. In the sixth O site, O(6) is bonded to one Na(3), one Na(4), two equivalent Na(2), and one Co(3) atom to form distorted ONa4Co trigonal bipyramids that share  a cornercorner with one O(1)Na2Co2 tetrahedra,  a cornercorner with one O(4)Na2Co2 tetrahedra, corners with two equivalent O(3)Na2Co2 tetrahedra, corners with two equivalent O(5)Na4Co trigonal bipyramids, corners with three equivalent O(6)Na4Co trigonal bipyramids,  an edgeedge with one O(1)Na2Co2 tetrahedra, edges with two equivalent O(7)Na4Co trigonal bipyramids, and edges with two equivalent O(8)Na4Co trigonal bipyramids. In the seventh O site, O(7) is bonded to one Na(1), one Na(2), two equivalent Na(3), and one Co(2) atom to form distorted ONa4Co trigonal bipyramids that share  a cornercorner with one O(1)Na2Co2 tetrahedra,  a cornercorner with one O(4)Na2Co2 tetrahedra, corners with two equivalent O(2)Na2Co2 tetrahedra, corners with two equivalent O(8)Na4Co trigonal bipyramids, corners with three equivalent O(7)Na4Co trigonal bipyramids,  an edgeedge with one O(4)Na2Co2 tetrahedra, edges with two equivalent O(5)Na4Co trigonal bipyramids, and edges with two equivalent O(6)Na4Co trigonal bipyramids. In the eighth O site, O(8) is bonded to one Na(1), one Na(2), two equivalent Na(4), and one Co(4) atom to form distorted ONa4Co trigonal bipyramids that share  a cornercorner with one O(2)Na2Co2 tetrahedra,  a cornercorner with one O(3)Na2Co2 tetrahedra, corners with two equivalent O(1)Na2Co2 tetrahedra, corners with two equivalent O(7)Na4Co trigonal bipyramids, corners with three equivalent O(8)Na4Co trigonal bipyramids,  an edgeedge with one O(3)Na2Co2 tetrahedra, edges with two equivalent O(5)Na4Co trigonal bipyramids, and edges with two equivalent O(6)Na4Co trigonal bipyramids. is represented by the CIF card [CIF]
data_Na2CoO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.063
_cell_length_b   6.020
_cell_length_c   11.283
_cell_angle_alpha   89.999
_cell_angle_beta   90.000
_cell_angle_gamma   90.419
_symmetry_Int_Tables_number   1
_cell_volume   343.890
_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
  Na  Na0  1  0.513  0.186  0.335  1.0
  Na  Na1  1  0.513  0.679  0.836  1.0
  Na  Na2  1  0.015  0.819  0.339  1.0
  Na  Na3  1  0.018  0.320  0.839  1.0
  Na  Na4  1  0.513  0.679  0.164  1.0
  Na  Na5  1  0.513  0.186  0.665  1.0
  Na  Na6  1  0.018  0.320  0.161  1.0
  Na  Na7  1  0.015  0.819  0.661  1.0
  Co  Co8  1  0.041  0.319  0.500  1.0
  Co  Co9  1  0.543  0.682  0.500  1.0
  Co  Co10  1  0.038  0.814  0.000  1.0
  Co  Co11  1  0.549  0.159  0.000  1.0
  O  O12  1  0.407  0.880  0.000  1.0
  O  O13  1  0.392  0.396  0.500  1.0
  O  O14  1  0.907  0.107  1.000  1.0
  O  O15  1  0.892  0.603  0.500  1.0
  O  O16  1  0.995  0.211  0.359  1.0
  O  O17  1  0.994  0.715  0.858  1.0
  O  O18  1  0.497  0.792  0.360  1.0
  O  O19  1  0.487  0.300  0.865  1.0
  O  O20  1  0.994  0.715  0.142  1.0
  O  O21  1  0.995  0.211  0.641  1.0
  O  O22  1  0.487  0.300  0.135  1.0
  O  O23  1  0.497  0.792  0.640  1.0
[/CIF]
.