The structure described by Na2CoO3 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(1) and four equivalent O(2) atoms. In the second Na site, Na(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Co(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, and edges with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-18°. In the third Na site, Na(3) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, and edges with six equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 18°. Co(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CoO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with three equivalent Na(3)O6 octahedra, and edges with three equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 14°. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Co(1) atoms to form a mixture of corner and edge-sharing ONa4Co2 octahedra. The corner-sharing octahedral tilt angles range from 0-13°. In the second O site, O(2) is bonded to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Co(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Co2 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2CoO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.188
_cell_length_b   5.188
_cell_length_c   5.645
_cell_angle_alpha   80.687
_cell_angle_beta   80.687
_cell_angle_gamma   119.837
_symmetry_Int_Tables_number   1
_cell_volume   124.737
_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  0.842  0.158  0.500  1.0
  Na  Na1  1  0.158  0.842  0.500  1.0
  Na  Na2  1  0.500  0.500  0.500  1.0
  Na  Na3  1  0.000  0.000  0.000  1.0
  Co  Co4  1  0.329  0.671  0.000  1.0
  Co  Co5  1  0.671  0.329  0.000  1.0
  O  O6  1  0.687  0.687  0.801  1.0
  O  O7  1  0.937  0.554  0.198  1.0
  O  O8  1  0.554  0.937  0.198  1.0
  O  O9  1  0.063  0.446  0.802  1.0
  O  O10  1  0.446  0.063  0.802  1.0
  O  O11  1  0.313  0.313  0.199  1.0
[/CIF]
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The structure described by Na2CoO3 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(1) and four equivalent O(2) atoms. In the second Na site, Na(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Co(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, and edges with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-18°. In the third Na site, Na(3) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, and edges with six equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 18°. Co(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CoO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with three equivalent Na(3)O6 octahedra, and edges with three equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 14°. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Co(1) atoms to form a mixture of corner and edge-sharing ONa4Co2 octahedra. The corner-sharing octahedral tilt angles range from 0-13°. In the second O site, O(2) is bonded to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Co(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Co2 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2CoO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.188
_cell_length_b   5.188
_cell_length_c   5.645
_cell_angle_alpha   80.687
_cell_angle_beta   80.687
_cell_angle_gamma   119.837
_symmetry_Int_Tables_number   1
_cell_volume   124.737
_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  0.842  0.158  0.500  1.0
  Na  Na1  1  0.158  0.842  0.500  1.0
  Na  Na2  1  0.500  0.500  0.500  1.0
  Na  Na3  1  0.000  0.000  0.000  1.0
  Co  Co4  1  0.329  0.671  0.000  1.0
  Co  Co5  1  0.671  0.329  0.000  1.0
  O  O6  1  0.687  0.687  0.801  1.0
  O  O7  1  0.937  0.554  0.198  1.0
  O  O8  1  0.554  0.937  0.198  1.0
  O  O9  1  0.063  0.446  0.802  1.0
  O  O10  1  0.446  0.063  0.802  1.0
  O  O11  1  0.313  0.313  0.199  1.0
[/CIF]
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