The crystal structure described by Na6CoO4 crystallizes in the tetragonal P4_2/nmc space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to four equivalent O(1) atoms to form NaO4 tetrahedra that share corners with four equivalent Co(1)O4 tetrahedra, corners with eight equivalent Na(2)O4 tetrahedra, edges with two equivalent Na(1)O4 tetrahedra, and edges with four equivalent Na(2)O4 tetrahedra. In the second Na site, Na(2) is bonded to four equivalent O(1) atoms to form distorted NaO4 tetrahedra that share corners with two equivalent Co(1)O4 tetrahedra, corners with four equivalent Na(1)O4 tetrahedra, corners with eight equivalent Na(2)O4 tetrahedra,  an edgeedge with one Co(1)O4 tetrahedra, edges with two equivalent Na(1)O4 tetrahedra, and edges with two equivalent Na(2)O4 tetrahedra. Co(1) is bonded to four equivalent O(1) atoms to form distorted CoO4 tetrahedra that share corners with eight equivalent Na(1)O4 tetrahedra, corners with eight equivalent Na(2)O4 tetrahedra, and edges with four equivalent Na(2)O4 tetrahedra. O(1) is bonded to two equivalent Na(1), four equivalent Na(2), and one Co(1) atom to form a mixture of distorted edge and corner-sharing ONa6Co pentagonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na6CoO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.475
_cell_length_b   7.479
_cell_length_c   7.479
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   306.309
_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
  Co  Co0  1  0.750  0.250  0.750  1.0
  Co  Co1  1  0.250  0.750  0.250  1.0
  Na  Na2  1  0.339  0.750  0.750  1.0
  Na  Na3  1  0.839  0.750  0.750  1.0
  Na  Na4  1  0.661  0.250  0.250  1.0
  Na  Na5  1  0.161  0.250  0.250  1.0
  Na  Na6  1  0.250  0.463  0.963  1.0
  Na  Na7  1  0.250  0.037  0.963  1.0
  Na  Na8  1  0.250  0.463  0.537  1.0
  Na  Na9  1  0.250  0.037  0.537  1.0
  Na  Na10  1  0.750  0.963  0.463  1.0
  Na  Na11  1  0.750  0.537  0.463  1.0
  Na  Na12  1  0.750  0.963  0.037  1.0
  Na  Na13  1  0.750  0.537  0.037  1.0
  O  O14  1  0.070  0.750  0.005  1.0
  O  O15  1  0.570  0.005  0.750  1.0
  O  O16  1  0.570  0.495  0.750  1.0
  O  O17  1  0.070  0.750  0.495  1.0
  O  O18  1  0.930  0.250  0.505  1.0
  O  O19  1  0.430  0.995  0.250  1.0
  O  O20  1  0.430  0.505  0.250  1.0
  O  O21  1  0.930  0.250  0.995  1.0
[/CIF]
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The crystal structure described by Na6CoO4 crystallizes in the tetragonal P4_2/nmc space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to four equivalent O(1) atoms to form NaO4 tetrahedra that share corners with four equivalent Co(1)O4 tetrahedra, corners with eight equivalent Na(2)O4 tetrahedra, edges with two equivalent Na(1)O4 tetrahedra, and edges with four equivalent Na(2)O4 tetrahedra. In the second Na site, Na(2) is bonded to four equivalent O(1) atoms to form distorted NaO4 tetrahedra that share corners with two equivalent Co(1)O4 tetrahedra, corners with four equivalent Na(1)O4 tetrahedra, corners with eight equivalent Na(2)O4 tetrahedra,  an edgeedge with one Co(1)O4 tetrahedra, edges with two equivalent Na(1)O4 tetrahedra, and edges with two equivalent Na(2)O4 tetrahedra. Co(1) is bonded to four equivalent O(1) atoms to form distorted CoO4 tetrahedra that share corners with eight equivalent Na(1)O4 tetrahedra, corners with eight equivalent Na(2)O4 tetrahedra, and edges with four equivalent Na(2)O4 tetrahedra. O(1) is bonded to two equivalent Na(1), four equivalent Na(2), and one Co(1) atom to form a mixture of distorted edge and corner-sharing ONa6Co pentagonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na6CoO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.475
_cell_length_b   7.479
_cell_length_c   7.479
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   306.309
_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
  Co  Co0  1  0.750  0.250  0.750  1.0
  Co  Co1  1  0.250  0.750  0.250  1.0
  Na  Na2  1  0.339  0.750  0.750  1.0
  Na  Na3  1  0.839  0.750  0.750  1.0
  Na  Na4  1  0.661  0.250  0.250  1.0
  Na  Na5  1  0.161  0.250  0.250  1.0
  Na  Na6  1  0.250  0.463  0.963  1.0
  Na  Na7  1  0.250  0.037  0.963  1.0
  Na  Na8  1  0.250  0.463  0.537  1.0
  Na  Na9  1  0.250  0.037  0.537  1.0
  Na  Na10  1  0.750  0.963  0.463  1.0
  Na  Na11  1  0.750  0.537  0.463  1.0
  Na  Na12  1  0.750  0.963  0.037  1.0
  Na  Na13  1  0.750  0.537  0.037  1.0
  O  O14  1  0.070  0.750  0.005  1.0
  O  O15  1  0.570  0.005  0.750  1.0
  O  O16  1  0.570  0.495  0.750  1.0
  O  O17  1  0.070  0.750  0.495  1.0
  O  O18  1  0.930  0.250  0.505  1.0
  O  O19  1  0.430  0.995  0.250  1.0
  O  O20  1  0.430  0.505  0.250  1.0
  O  O21  1  0.930  0.250  0.995  1.0
[/CIF]
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