The material structure described by Na14Co2O9 crystallizes in the trigonal P-3 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1) and three equivalent O(3) atoms to form NaO4 tetrahedra that share  a cornercorner with one Na(1)O4 tetrahedra, corners with three equivalent Na(2)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, corners with six equivalent Na(3)O4 tetrahedra, edges with three equivalent Na(2)O4 tetrahedra, and edges with three equivalent Na(3)O4 tetrahedra. In the second Na site, Na(2) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form distorted NaO4 tetrahedra that share  a cornercorner with one Na(1)O4 tetrahedra,  a cornercorner with one Co(1)O4 tetrahedra, corners with four equivalent Na(3)O4 tetrahedra, corners with nine equivalent Na(2)O4 tetrahedra,  an edgeedge with one Na(1)O4 tetrahedra,  an edgeedge with one Co(1)O4 tetrahedra, and edges with three equivalent Na(2)O4 tetrahedra. In the third Na site, Na(3) is bonded to four equivalent O(3) atoms to form NaO4 tetrahedra that share corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Co(1)O4 tetrahedra, corners with four equivalent Na(2)O4 tetrahedra, corners with six equivalent Na(3)O4 tetrahedra,  an edgeedge with one Na(1)O4 tetrahedra,  an edgeedge with one Co(1)O4 tetrahedra, and edges with three equivalent Na(3)O4 tetrahedra. Co(1) is bonded to one O(2) and three equivalent O(3) atoms to form CoO4 tetrahedra that share corners with three equivalent Na(1)O4 tetrahedra, corners with three equivalent Na(2)O4 tetrahedra, corners with six equivalent Na(3)O4 tetrahedra, edges with three equivalent Na(2)O4 tetrahedra, and edges with three equivalent Na(3)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a body-centered cubic geometry to two equivalent Na(1) and six equivalent Na(2) atoms. In the second O site, O(2) is bonded in a 7-coordinate geometry to six equivalent Na(2) and one Co(1) atom. In the third O site, O(3) is bonded to one Na(1), one Na(2), four equivalent Na(3), and one Co(1) atom to form a mixture of distorted corner and edge-sharing ONa6Co pentagonal bipyramids. is represented by the CIF card [CIF]
data_Na14Co2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.660
_cell_length_b   6.660
_cell_length_c   9.382
_cell_angle_alpha   90.007
_cell_angle_beta   89.995
_cell_angle_gamma   120.001
_symmetry_Int_Tables_number   1
_cell_volume   360.363
_cell_formula_units_Z   1
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
  Co  Co0  1  0.333  0.667  0.262  1.0
  Co  Co1  1  0.667  0.333  0.738  1.0
  Na  Na2  1  0.000  0.000  0.251  1.0
  Na  Na3  1  1.000  1.000  0.749  1.0
  Na  Na4  1  0.639  0.964  0.908  1.0
  Na  Na5  1  0.036  0.676  0.908  1.0
  Na  Na6  1  0.324  0.361  0.908  1.0
  Na  Na7  1  0.676  0.639  0.092  1.0
  Na  Na8  1  0.964  0.324  0.092  1.0
  Na  Na9  1  0.361  0.036  0.092  1.0
  Na  Na10  1  0.623  0.688  0.593  1.0
  Na  Na11  1  0.312  0.935  0.593  1.0
  Na  Na12  1  0.935  0.623  0.407  1.0
  Na  Na13  1  0.065  0.377  0.593  1.0
  Na  Na14  1  0.688  0.065  0.407  1.0
  Na  Na15  1  0.377  0.312  0.407  1.0
  O  O16  1  0.000  0.000  1.000  1.0
  O  O17  1  0.333  0.667  0.045  1.0
  O  O18  1  0.667  0.333  0.955  1.0
  O  O19  1  0.637  0.696  0.336  1.0
  O  O20  1  0.304  0.941  0.336  1.0
  O  O21  1  0.941  0.637  0.664  1.0
  O  O22  1  0.059  0.363  0.336  1.0
  O  O23  1  0.696  0.059  0.664  1.0
  O  O24  1  0.363  0.304  0.664  1.0
[/CIF]
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The material structure described by Na14Co2O9 crystallizes in the trigonal P-3 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1) and three equivalent O(3) atoms to form NaO4 tetrahedra that share  a cornercorner with one Na(1)O4 tetrahedra, corners with three equivalent Na(2)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, corners with six equivalent Na(3)O4 tetrahedra, edges with three equivalent Na(2)O4 tetrahedra, and edges with three equivalent Na(3)O4 tetrahedra. In the second Na site, Na(2) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form distorted NaO4 tetrahedra that share  a cornercorner with one Na(1)O4 tetrahedra,  a cornercorner with one Co(1)O4 tetrahedra, corners with four equivalent Na(3)O4 tetrahedra, corners with nine equivalent Na(2)O4 tetrahedra,  an edgeedge with one Na(1)O4 tetrahedra,  an edgeedge with one Co(1)O4 tetrahedra, and edges with three equivalent Na(2)O4 tetrahedra. In the third Na site, Na(3) is bonded to four equivalent O(3) atoms to form NaO4 tetrahedra that share corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Co(1)O4 tetrahedra, corners with four equivalent Na(2)O4 tetrahedra, corners with six equivalent Na(3)O4 tetrahedra,  an edgeedge with one Na(1)O4 tetrahedra,  an edgeedge with one Co(1)O4 tetrahedra, and edges with three equivalent Na(3)O4 tetrahedra. Co(1) is bonded to one O(2) and three equivalent O(3) atoms to form CoO4 tetrahedra that share corners with three equivalent Na(1)O4 tetrahedra, corners with three equivalent Na(2)O4 tetrahedra, corners with six equivalent Na(3)O4 tetrahedra, edges with three equivalent Na(2)O4 tetrahedra, and edges with three equivalent Na(3)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a body-centered cubic geometry to two equivalent Na(1) and six equivalent Na(2) atoms. In the second O site, O(2) is bonded in a 7-coordinate geometry to six equivalent Na(2) and one Co(1) atom. In the third O site, O(3) is bonded to one Na(1), one Na(2), four equivalent Na(3), and one Co(1) atom to form a mixture of distorted corner and edge-sharing ONa6Co pentagonal bipyramids. is represented by the CIF card [CIF]
data_Na14Co2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.660
_cell_length_b   6.660
_cell_length_c   9.382
_cell_angle_alpha   90.007
_cell_angle_beta   89.995
_cell_angle_gamma   120.001
_symmetry_Int_Tables_number   1
_cell_volume   360.363
_cell_formula_units_Z   1
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
  Co  Co0  1  0.333  0.667  0.262  1.0
  Co  Co1  1  0.667  0.333  0.738  1.0
  Na  Na2  1  0.000  0.000  0.251  1.0
  Na  Na3  1  1.000  1.000  0.749  1.0
  Na  Na4  1  0.639  0.964  0.908  1.0
  Na  Na5  1  0.036  0.676  0.908  1.0
  Na  Na6  1  0.324  0.361  0.908  1.0
  Na  Na7  1  0.676  0.639  0.092  1.0
  Na  Na8  1  0.964  0.324  0.092  1.0
  Na  Na9  1  0.361  0.036  0.092  1.0
  Na  Na10  1  0.623  0.688  0.593  1.0
  Na  Na11  1  0.312  0.935  0.593  1.0
  Na  Na12  1  0.935  0.623  0.407  1.0
  Na  Na13  1  0.065  0.377  0.593  1.0
  Na  Na14  1  0.688  0.065  0.407  1.0
  Na  Na15  1  0.377  0.312  0.407  1.0
  O  O16  1  0.000  0.000  1.000  1.0
  O  O17  1  0.333  0.667  0.045  1.0
  O  O18  1  0.667  0.333  0.955  1.0
  O  O19  1  0.637  0.696  0.336  1.0
  O  O20  1  0.304  0.941  0.336  1.0
  O  O21  1  0.941  0.637  0.664  1.0
  O  O22  1  0.059  0.363  0.336  1.0
  O  O23  1  0.696  0.059  0.664  1.0
  O  O24  1  0.363  0.304  0.664  1.0
[/CIF]
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