The material described by Na4(CoO2)7 crystallizes in the hexagonal P6_3/m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to six equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), two equivalent O(3), and three equivalent O(2) atoms to form edge-sharing CoO6 octahedra. In the second Co site, Co(2) is bonded to six equivalent O(3) atoms to form edge-sharing CoO6 octahedra. There are three inequivalent O sites. In the first O site, O(3) is bonded to one Na(1), one Na(2), one Co(2), and two equivalent Co(1) atoms to form distorted ONa2Co3 trigonal bipyramids that share corners with two equivalent O(1)Na3Co3 octahedra, corners with three equivalent O(3)Na2Co3 trigonal bipyramids, corners with four equivalent O(2)NaCo3 trigonal pyramids,  an edgeedge with one O(1)Na3Co3 octahedra, edges with five equivalent O(3)Na2Co3 trigonal bipyramids, and edges with two equivalent O(2)NaCo3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 0-52°. In the second O site, O(1) is bonded to three equivalent Na(2) and three equivalent Co(1) atoms to form distorted ONa3Co3 octahedra that share corners with six equivalent O(3)Na2Co3 trigonal bipyramids, corners with three equivalent O(2)NaCo3 trigonal pyramids, edges with three equivalent O(3)Na2Co3 trigonal bipyramids, edges with six equivalent O(2)NaCo3 trigonal pyramids, and  a faceface with one O(1)Na3Co3 octahedra. In the third O site, O(2) is bonded to one Na(2) and three equivalent Co(1) atoms to form ONaCo3 trigonal pyramids that share  a cornercorner with one O(1)Na3Co3 octahedra, corners with four equivalent O(3)Na2Co3 trigonal bipyramids, corners with five equivalent O(2)NaCo3 trigonal pyramids, edges with two equivalent O(1)Na3Co3 octahedra, edges with two equivalent O(3)Na2Co3 trigonal bipyramids, and  an edgeedge with one O(2)NaCo3 trigonal pyramid. The corner-sharing octahedral tilt angles are 44°. is represented by the CIF file [CIF]
data_Na4(CoO2)7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.502
_cell_length_b   7.502
_cell_length_c   11.136
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   542.813
_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  0.000  0.000  0.250  1.0
  Na  Na1  1  0.000  0.000  0.750  1.0
  Na  Na2  1  0.452  0.410  0.250  1.0
  Na  Na3  1  0.042  0.452  0.750  1.0
  Na  Na4  1  0.410  0.958  0.750  1.0
  Na  Na5  1  0.590  0.042  0.250  1.0
  Na  Na6  1  0.958  0.548  0.250  1.0
  Na  Na7  1  0.548  0.590  0.750  1.0
  Co  Co8  1  0.572  0.857  0.998  1.0
  Co  Co9  1  0.428  0.143  0.498  1.0
  Co  Co10  1  0.857  0.285  0.498  1.0
  Co  Co11  1  0.285  0.428  0.998  1.0
  Co  Co12  1  0.000  0.000  0.500  1.0
  Co  Co13  1  0.000  0.000  0.000  1.0
  Co  Co14  1  0.143  0.715  0.998  1.0
  Co  Co15  1  0.715  0.572  0.498  1.0
  Co  Co16  1  0.715  0.572  0.002  1.0
  Co  Co17  1  0.143  0.715  0.502  1.0
  Co  Co18  1  0.572  0.857  0.502  1.0
  Co  Co19  1  0.428  0.143  0.002  1.0
  Co  Co20  1  0.857  0.285  0.002  1.0
  Co  Co21  1  0.285  0.428  0.502  1.0
  O  O22  1  0.333  0.667  0.594  1.0
  O  O23  1  0.667  0.333  0.094  1.0
  O  O24  1  0.667  0.333  0.406  1.0
  O  O25  1  0.333  0.667  0.906  1.0
  O  O26  1  0.096  0.477  0.416  1.0
  O  O27  1  0.619  0.096  0.916  1.0
  O  O28  1  0.477  0.381  0.916  1.0
  O  O29  1  0.523  0.619  0.416  1.0
  O  O30  1  0.381  0.904  0.416  1.0
  O  O31  1  0.904  0.523  0.916  1.0
  O  O32  1  0.904  0.523  0.584  1.0
  O  O33  1  0.381  0.904  0.084  1.0
  O  O34  1  0.523  0.619  0.084  1.0
  O  O35  1  0.477  0.381  0.584  1.0
  O  O36  1  0.619  0.096  0.584  1.0
  O  O37  1  0.096  0.477  0.084  1.0
  O  O38  1  0.238  0.193  0.411  1.0
  O  O39  1  0.046  0.238  0.911  1.0
  O  O40  1  0.193  0.954  0.911  1.0
  O  O41  1  0.807  0.046  0.411  1.0
  O  O42  1  0.954  0.762  0.411  1.0
  O  O43  1  0.762  0.807  0.911  1.0
  O  O44  1  0.238  0.193  0.089  1.0
  O  O45  1  0.046  0.238  0.589  1.0
  O  O46  1  0.193  0.954  0.589  1.0
  O  O47  1  0.807  0.046  0.089  1.0
  O  O48  1  0.954  0.762  0.089  1.0
  O  O49  1  0.762  0.807  0.589  1.0
[/CIF]
.
The material described by Na4(CoO2)7 crystallizes in the hexagonal P6_3/m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to six equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), two equivalent O(3), and three equivalent O(2) atoms to form edge-sharing CoO6 octahedra. In the second Co site, Co(2) is bonded to six equivalent O(3) atoms to form edge-sharing CoO6 octahedra. There are three inequivalent O sites. In the first O site, O(3) is bonded to one Na(1), one Na(2), one Co(2), and two equivalent Co(1) atoms to form distorted ONa2Co3 trigonal bipyramids that share corners with two equivalent O(1)Na3Co3 octahedra, corners with three equivalent O(3)Na2Co3 trigonal bipyramids, corners with four equivalent O(2)NaCo3 trigonal pyramids,  an edgeedge with one O(1)Na3Co3 octahedra, edges with five equivalent O(3)Na2Co3 trigonal bipyramids, and edges with two equivalent O(2)NaCo3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 0-52°. In the second O site, O(1) is bonded to three equivalent Na(2) and three equivalent Co(1) atoms to form distorted ONa3Co3 octahedra that share corners with six equivalent O(3)Na2Co3 trigonal bipyramids, corners with three equivalent O(2)NaCo3 trigonal pyramids, edges with three equivalent O(3)Na2Co3 trigonal bipyramids, edges with six equivalent O(2)NaCo3 trigonal pyramids, and  a faceface with one O(1)Na3Co3 octahedra. In the third O site, O(2) is bonded to one Na(2) and three equivalent Co(1) atoms to form ONaCo3 trigonal pyramids that share  a cornercorner with one O(1)Na3Co3 octahedra, corners with four equivalent O(3)Na2Co3 trigonal bipyramids, corners with five equivalent O(2)NaCo3 trigonal pyramids, edges with two equivalent O(1)Na3Co3 octahedra, edges with two equivalent O(3)Na2Co3 trigonal bipyramids, and  an edgeedge with one O(2)NaCo3 trigonal pyramid. The corner-sharing octahedral tilt angles are 44°. is represented by the CIF file [CIF]
data_Na4(CoO2)7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.502
_cell_length_b   7.502
_cell_length_c   11.136
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   542.813
_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  0.000  0.000  0.250  1.0
  Na  Na1  1  0.000  0.000  0.750  1.0
  Na  Na2  1  0.452  0.410  0.250  1.0
  Na  Na3  1  0.042  0.452  0.750  1.0
  Na  Na4  1  0.410  0.958  0.750  1.0
  Na  Na5  1  0.590  0.042  0.250  1.0
  Na  Na6  1  0.958  0.548  0.250  1.0
  Na  Na7  1  0.548  0.590  0.750  1.0
  Co  Co8  1  0.572  0.857  0.998  1.0
  Co  Co9  1  0.428  0.143  0.498  1.0
  Co  Co10  1  0.857  0.285  0.498  1.0
  Co  Co11  1  0.285  0.428  0.998  1.0
  Co  Co12  1  0.000  0.000  0.500  1.0
  Co  Co13  1  0.000  0.000  0.000  1.0
  Co  Co14  1  0.143  0.715  0.998  1.0
  Co  Co15  1  0.715  0.572  0.498  1.0
  Co  Co16  1  0.715  0.572  0.002  1.0
  Co  Co17  1  0.143  0.715  0.502  1.0
  Co  Co18  1  0.572  0.857  0.502  1.0
  Co  Co19  1  0.428  0.143  0.002  1.0
  Co  Co20  1  0.857  0.285  0.002  1.0
  Co  Co21  1  0.285  0.428  0.502  1.0
  O  O22  1  0.333  0.667  0.594  1.0
  O  O23  1  0.667  0.333  0.094  1.0
  O  O24  1  0.667  0.333  0.406  1.0
  O  O25  1  0.333  0.667  0.906  1.0
  O  O26  1  0.096  0.477  0.416  1.0
  O  O27  1  0.619  0.096  0.916  1.0
  O  O28  1  0.477  0.381  0.916  1.0
  O  O29  1  0.523  0.619  0.416  1.0
  O  O30  1  0.381  0.904  0.416  1.0
  O  O31  1  0.904  0.523  0.916  1.0
  O  O32  1  0.904  0.523  0.584  1.0
  O  O33  1  0.381  0.904  0.084  1.0
  O  O34  1  0.523  0.619  0.084  1.0
  O  O35  1  0.477  0.381  0.584  1.0
  O  O36  1  0.619  0.096  0.584  1.0
  O  O37  1  0.096  0.477  0.084  1.0
  O  O38  1  0.238  0.193  0.411  1.0
  O  O39  1  0.046  0.238  0.911  1.0
  O  O40  1  0.193  0.954  0.911  1.0
  O  O41  1  0.807  0.046  0.411  1.0
  O  O42  1  0.954  0.762  0.411  1.0
  O  O43  1  0.762  0.807  0.911  1.0
  O  O44  1  0.238  0.193  0.089  1.0
  O  O45  1  0.046  0.238  0.589  1.0
  O  O46  1  0.193  0.954  0.589  1.0
  O  O47  1  0.807  0.046  0.089  1.0
  O  O48  1  0.954  0.762  0.089  1.0
  O  O49  1  0.762  0.807  0.589  1.0
[/CIF]
.