The compound described by Na2CoO3 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Co(1)O4 tetrahedra, edges with two equivalent Na(1)O6 octahedra, edges with five equivalent Na(2)O6 octahedra, and edges with two equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 9-33°. In the second Na site, Na(2) is bonded to one O(1), two equivalent O(3), and three equivalent O(2) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with four equivalent Na(2)O6 octahedra, corners with three equivalent Co(1)O4 tetrahedra, edges with two equivalent Na(2)O6 octahedra, edges with five equivalent Na(1)O6 octahedra, and edges with two equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 9-44°. Co(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form CoO4 tetrahedra that share corners with three equivalent Na(2)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, and  an edgeedge with one Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 10-77°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), two equivalent Na(1), and two equivalent Co(1) atoms to form distorted ONa3Co2 square pyramids that share  a cornercorner with one O(2)Na5Co octahedra, corners with two equivalent O(1)Na3Co2 square pyramids, edges with four equivalent O(2)Na5Co octahedra, and  an edgeedge with one O(1)Na3Co2 square pyramid. The corner-sharing octahedral tilt angles are 86°. In the second O site, O(2) is bonded to two equivalent Na(1), three equivalent Na(2), and one Co(1) atom to form distorted ONa5Co octahedra that share corners with four equivalent O(2)Na5Co octahedra,  a cornercorner with one O(1)Na3Co2 square pyramid, edges with two equivalent O(2)Na5Co octahedra, and edges with four equivalent O(1)Na3Co2 square pyramids. The corner-sharing octahedral tilt angles range from 11-15°. In the third O site, O(3) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Na(2), and one Co(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2CoO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.008
_cell_length_b   4.956
_cell_length_c   6.430
_cell_angle_alpha   85.929
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   318.105
_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  0.730  0.257  0.858  1.0
  Na  Na1  1  0.770  0.257  0.358  1.0
  Na  Na2  1  0.400  0.273  0.885  1.0
  Na  Na3  1  0.100  0.273  0.385  1.0
  Na  Na4  1  0.900  0.727  0.615  1.0
  Na  Na5  1  0.600  0.727  0.115  1.0
  Na  Na6  1  0.230  0.743  0.642  1.0
  Na  Na7  1  0.270  0.743  0.142  1.0
  Co  Co8  1  0.035  0.166  0.841  1.0
  Co  Co9  1  0.465  0.166  0.341  1.0
  Co  Co10  1  0.535  0.834  0.659  1.0
  Co  Co11  1  0.965  0.834  0.159  1.0
  O  O12  1  0.550  0.216  0.592  1.0
  O  O13  1  0.950  0.216  0.092  1.0
  O  O14  1  0.917  0.236  0.642  1.0
  O  O15  1  0.583  0.236  0.142  1.0
  O  O16  1  0.188  0.258  0.736  1.0
  O  O17  1  0.312  0.258  0.236  1.0
  O  O18  1  0.688  0.742  0.764  1.0
  O  O19  1  0.812  0.742  0.264  1.0
  O  O20  1  0.417  0.764  0.858  1.0
  O  O21  1  0.083  0.764  0.358  1.0
  O  O22  1  0.050  0.784  0.908  1.0
  O  O23  1  0.450  0.784  0.408  1.0
[/CIF]
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The compound described by Na2CoO3 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Co(1)O4 tetrahedra, edges with two equivalent Na(1)O6 octahedra, edges with five equivalent Na(2)O6 octahedra, and edges with two equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 9-33°. In the second Na site, Na(2) is bonded to one O(1), two equivalent O(3), and three equivalent O(2) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with four equivalent Na(2)O6 octahedra, corners with three equivalent Co(1)O4 tetrahedra, edges with two equivalent Na(2)O6 octahedra, edges with five equivalent Na(1)O6 octahedra, and edges with two equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 9-44°. Co(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form CoO4 tetrahedra that share corners with three equivalent Na(2)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, and  an edgeedge with one Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 10-77°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), two equivalent Na(1), and two equivalent Co(1) atoms to form distorted ONa3Co2 square pyramids that share  a cornercorner with one O(2)Na5Co octahedra, corners with two equivalent O(1)Na3Co2 square pyramids, edges with four equivalent O(2)Na5Co octahedra, and  an edgeedge with one O(1)Na3Co2 square pyramid. The corner-sharing octahedral tilt angles are 86°. In the second O site, O(2) is bonded to two equivalent Na(1), three equivalent Na(2), and one Co(1) atom to form distorted ONa5Co octahedra that share corners with four equivalent O(2)Na5Co octahedra,  a cornercorner with one O(1)Na3Co2 square pyramid, edges with two equivalent O(2)Na5Co octahedra, and edges with four equivalent O(1)Na3Co2 square pyramids. The corner-sharing octahedral tilt angles range from 11-15°. In the third O site, O(3) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Na(2), and one Co(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2CoO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.008
_cell_length_b   4.956
_cell_length_c   6.430
_cell_angle_alpha   85.929
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   318.105
_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  0.730  0.257  0.858  1.0
  Na  Na1  1  0.770  0.257  0.358  1.0
  Na  Na2  1  0.400  0.273  0.885  1.0
  Na  Na3  1  0.100  0.273  0.385  1.0
  Na  Na4  1  0.900  0.727  0.615  1.0
  Na  Na5  1  0.600  0.727  0.115  1.0
  Na  Na6  1  0.230  0.743  0.642  1.0
  Na  Na7  1  0.270  0.743  0.142  1.0
  Co  Co8  1  0.035  0.166  0.841  1.0
  Co  Co9  1  0.465  0.166  0.341  1.0
  Co  Co10  1  0.535  0.834  0.659  1.0
  Co  Co11  1  0.965  0.834  0.159  1.0
  O  O12  1  0.550  0.216  0.592  1.0
  O  O13  1  0.950  0.216  0.092  1.0
  O  O14  1  0.917  0.236  0.642  1.0
  O  O15  1  0.583  0.236  0.142  1.0
  O  O16  1  0.188  0.258  0.736  1.0
  O  O17  1  0.312  0.258  0.236  1.0
  O  O18  1  0.688  0.742  0.764  1.0
  O  O19  1  0.812  0.742  0.264  1.0
  O  O20  1  0.417  0.764  0.858  1.0
  O  O21  1  0.083  0.764  0.358  1.0
  O  O22  1  0.050  0.784  0.908  1.0
  O  O23  1  0.450  0.784  0.408  1.0
[/CIF]
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