The compound described by NaCo2O3 crystallizes in the triclinic P1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(2), one O(4), one O(6), and two equivalent O(1) atoms. In the second Na site, Na(2) is bonded to one O(1), one O(3), one O(5), and two equivalent O(2) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(4)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, corners with three equivalent Co(3)O4 tetrahedra, corners with two equivalent Na(2)O5 trigonal bipyramids,  an edgeedge with one Co(2)O4 tetrahedra, and  an edgeedge with one Co(4)O4 tetrahedra. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(3), one O(5), and one O(6) atom to form CoO4 tetrahedra that share corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(4)O4 tetrahedra, corners with three equivalent Co(3)O4 tetrahedra, and corners with three equivalent Na(2)O5 trigonal bipyramids. In the second Co site, Co(2) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form CoO4 tetrahedra that share corners with two equivalent Co(1)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra, corners with three equivalent Co(4)O4 tetrahedra,  a cornercorner with one Na(2)O5 trigonal bipyramid, and  an edgeedge with one Na(2)O5 trigonal bipyramid. In the third Co site, Co(3) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form CoO4 tetrahedra that share corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(4)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, and corners with three equivalent Na(2)O5 trigonal bipyramids. In the fourth Co site, Co(4) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form CoO4 tetrahedra that share corners with two equivalent Co(1)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra, corners with three equivalent Co(2)O4 tetrahedra,  a cornercorner with one Na(2)O5 trigonal bipyramid, and  an edgeedge with one Na(2)O5 trigonal bipyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Na(2), two equivalent Na(1), one Co(1), and one Co(3) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Co(2), and one Co(4) atom. In the third O site, O(3) is bonded to one Na(2), one Co(1), one Co(3), and one Co(4) atom to form distorted corner-sharing ONaCo3 trigonal pyramids. In the fourth O site, O(4) is bonded to one Na(1), one Co(2), one Co(3), and one Co(4) atom to form corner-sharing ONaCo3 tetrahedra. In the fifth O site, O(5) is bonded to one Na(2), one Co(1), one Co(2), and one Co(3) atom to form distorted corner-sharing ONaCo3 trigonal pyramids. In the sixth O site, O(6) is bonded to one Na(1), one Co(1), one Co(2), and one Co(4) atom to form corner-sharing ONaCo3 tetrahedra. is represented by the CIF file [CIF]
data_NaCo2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.224
_cell_length_b   5.907
_cell_length_c   5.896
_cell_angle_alpha   120.812
_cell_angle_beta   90.206
_cell_angle_gamma   90.069
_symmetry_Int_Tables_number   1
_cell_volume   156.244
_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  0.998  0.326  0.326  1.0
  Na  Na1  1  0.497  0.675  0.675  1.0
  Co  Co2  1  0.519  0.996  0.335  1.0
  Co  Co3  1  0.014  0.671  0.006  1.0
  Co  Co4  1  0.521  0.335  0.995  1.0
  Co  Co5  1  0.014  0.005  0.671  1.0
  O  O6  1  0.464  0.261  0.261  1.0
  O  O7  1  0.959  0.711  0.711  1.0
  O  O8  1  0.392  0.063  0.660  1.0
  O  O9  1  0.877  0.340  0.957  1.0
  O  O10  1  0.392  0.660  0.064  1.0
  O  O11  1  0.876  0.957  0.340  1.0
[/CIF]
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The compound described by NaCo2O3 crystallizes in the triclinic P1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(2), one O(4), one O(6), and two equivalent O(1) atoms. In the second Na site, Na(2) is bonded to one O(1), one O(3), one O(5), and two equivalent O(2) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(4)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, corners with three equivalent Co(3)O4 tetrahedra, corners with two equivalent Na(2)O5 trigonal bipyramids,  an edgeedge with one Co(2)O4 tetrahedra, and  an edgeedge with one Co(4)O4 tetrahedra. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(3), one O(5), and one O(6) atom to form CoO4 tetrahedra that share corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(4)O4 tetrahedra, corners with three equivalent Co(3)O4 tetrahedra, and corners with three equivalent Na(2)O5 trigonal bipyramids. In the second Co site, Co(2) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form CoO4 tetrahedra that share corners with two equivalent Co(1)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra, corners with three equivalent Co(4)O4 tetrahedra,  a cornercorner with one Na(2)O5 trigonal bipyramid, and  an edgeedge with one Na(2)O5 trigonal bipyramid. In the third Co site, Co(3) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form CoO4 tetrahedra that share corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(4)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, and corners with three equivalent Na(2)O5 trigonal bipyramids. In the fourth Co site, Co(4) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form CoO4 tetrahedra that share corners with two equivalent Co(1)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra, corners with three equivalent Co(2)O4 tetrahedra,  a cornercorner with one Na(2)O5 trigonal bipyramid, and  an edgeedge with one Na(2)O5 trigonal bipyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Na(2), two equivalent Na(1), one Co(1), and one Co(3) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Co(2), and one Co(4) atom. In the third O site, O(3) is bonded to one Na(2), one Co(1), one Co(3), and one Co(4) atom to form distorted corner-sharing ONaCo3 trigonal pyramids. In the fourth O site, O(4) is bonded to one Na(1), one Co(2), one Co(3), and one Co(4) atom to form corner-sharing ONaCo3 tetrahedra. In the fifth O site, O(5) is bonded to one Na(2), one Co(1), one Co(2), and one Co(3) atom to form distorted corner-sharing ONaCo3 trigonal pyramids. In the sixth O site, O(6) is bonded to one Na(1), one Co(1), one Co(2), and one Co(4) atom to form corner-sharing ONaCo3 tetrahedra. is represented by the CIF file [CIF]
data_NaCo2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.224
_cell_length_b   5.907
_cell_length_c   5.896
_cell_angle_alpha   120.812
_cell_angle_beta   90.206
_cell_angle_gamma   90.069
_symmetry_Int_Tables_number   1
_cell_volume   156.244
_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  0.998  0.326  0.326  1.0
  Na  Na1  1  0.497  0.675  0.675  1.0
  Co  Co2  1  0.519  0.996  0.335  1.0
  Co  Co3  1  0.014  0.671  0.006  1.0
  Co  Co4  1  0.521  0.335  0.995  1.0
  Co  Co5  1  0.014  0.005  0.671  1.0
  O  O6  1  0.464  0.261  0.261  1.0
  O  O7  1  0.959  0.711  0.711  1.0
  O  O8  1  0.392  0.063  0.660  1.0
  O  O9  1  0.877  0.340  0.957  1.0
  O  O10  1  0.392  0.660  0.064  1.0
  O  O11  1  0.876  0.957  0.340  1.0
[/CIF]
.