The structure described by Na2CoO3 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NaO5 trigonal bipyramids that share corners with three equivalent Co(1)O4 tetrahedra, corners with two equivalent Na(2)O4 trigonal pyramids, edges with two equivalent Co(1)O4 tetrahedra, edges with two equivalent Na(1)O5 trigonal bipyramids, and edges with two equivalent Na(2)O4 trigonal pyramids. In the second Na site, Na(2) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form NaO4 trigonal pyramids that share corners with five equivalent Co(1)O4 tetrahedra, corners with two equivalent Na(1)O5 trigonal bipyramids, edges with two equivalent Na(1)O5 trigonal bipyramids, and  an edgeedge with one Na(2)O4 trigonal pyramid. Co(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form CoO4 tetrahedra that share corners with three equivalent Na(1)O5 trigonal bipyramids, corners with five equivalent Na(2)O4 trigonal pyramids,  an edgeedge with one Co(1)O4 tetrahedra, and edges with two equivalent Na(1)O5 trigonal bipyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), two equivalent Na(2), and one Co(1) atom to form distorted ONa3Co trigonal pyramids that share corners with two equivalent O(3)Na3Co2 trigonal bipyramids, edges with two equivalent O(3)Na3Co2 trigonal bipyramids, and  an edgeedge with one O(1)Na3Co trigonal pyramid. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(2), two equivalent Na(1), and one Co(1) atom. In the third O site, O(3) is bonded to one Na(2), two equivalent Na(1), and two equivalent Co(1) atoms to form distorted ONa3Co2 trigonal bipyramids that share corners with two equivalent O(1)Na3Co trigonal pyramids, edges with two equivalent O(3)Na3Co2 trigonal bipyramids, and edges with two equivalent O(1)Na3Co trigonal pyramids. is represented by the CIF card [CIF]
data_Na2CoO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.421
_cell_length_b   5.988
_cell_length_c   6.606
_cell_angle_alpha   111.780
_cell_angle_beta   95.488
_cell_angle_gamma   96.241
_symmetry_Int_Tables_number   1
_cell_volume   195.786
_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
  Na  Na0  1  0.939  0.753  0.572  1.0
  Na  Na1  1  0.784  0.777  0.016  1.0
  Na  Na2  1  0.216  0.223  0.984  1.0
  Na  Na3  1  0.061  0.247  0.428  1.0
  Co  Co4  1  0.650  0.166  0.667  1.0
  Co  Co5  1  0.350  0.834  0.333  1.0
  O  O6  1  0.786  0.076  0.866  1.0
  O  O7  1  0.789  0.449  0.687  1.0
  O  O8  1  0.694  0.928  0.379  1.0
  O  O9  1  0.306  0.072  0.621  1.0
  O  O10  1  0.211  0.551  0.313  1.0
  O  O11  1  0.214  0.924  0.134  1.0
[/CIF]
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The structure described by Na2CoO3 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NaO5 trigonal bipyramids that share corners with three equivalent Co(1)O4 tetrahedra, corners with two equivalent Na(2)O4 trigonal pyramids, edges with two equivalent Co(1)O4 tetrahedra, edges with two equivalent Na(1)O5 trigonal bipyramids, and edges with two equivalent Na(2)O4 trigonal pyramids. In the second Na site, Na(2) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form NaO4 trigonal pyramids that share corners with five equivalent Co(1)O4 tetrahedra, corners with two equivalent Na(1)O5 trigonal bipyramids, edges with two equivalent Na(1)O5 trigonal bipyramids, and  an edgeedge with one Na(2)O4 trigonal pyramid. Co(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form CoO4 tetrahedra that share corners with three equivalent Na(1)O5 trigonal bipyramids, corners with five equivalent Na(2)O4 trigonal pyramids,  an edgeedge with one Co(1)O4 tetrahedra, and edges with two equivalent Na(1)O5 trigonal bipyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), two equivalent Na(2), and one Co(1) atom to form distorted ONa3Co trigonal pyramids that share corners with two equivalent O(3)Na3Co2 trigonal bipyramids, edges with two equivalent O(3)Na3Co2 trigonal bipyramids, and  an edgeedge with one O(1)Na3Co trigonal pyramid. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(2), two equivalent Na(1), and one Co(1) atom. In the third O site, O(3) is bonded to one Na(2), two equivalent Na(1), and two equivalent Co(1) atoms to form distorted ONa3Co2 trigonal bipyramids that share corners with two equivalent O(1)Na3Co trigonal pyramids, edges with two equivalent O(3)Na3Co2 trigonal bipyramids, and edges with two equivalent O(1)Na3Co trigonal pyramids. is represented by the CIF card [CIF]
data_Na2CoO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.421
_cell_length_b   5.988
_cell_length_c   6.606
_cell_angle_alpha   111.780
_cell_angle_beta   95.488
_cell_angle_gamma   96.241
_symmetry_Int_Tables_number   1
_cell_volume   195.786
_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
  Na  Na0  1  0.939  0.753  0.572  1.0
  Na  Na1  1  0.784  0.777  0.016  1.0
  Na  Na2  1  0.216  0.223  0.984  1.0
  Na  Na3  1  0.061  0.247  0.428  1.0
  Co  Co4  1  0.650  0.166  0.667  1.0
  Co  Co5  1  0.350  0.834  0.333  1.0
  O  O6  1  0.786  0.076  0.866  1.0
  O  O7  1  0.789  0.449  0.687  1.0
  O  O8  1  0.694  0.928  0.379  1.0
  O  O9  1  0.306  0.072  0.621  1.0
  O  O10  1  0.211  0.551  0.313  1.0
  O  O11  1  0.214  0.924  0.134  1.0
[/CIF]
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