The crystal structure described by Na8Mg(CoO4)2 crystallizes in the triclinic P1 space group. There are eight inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(8) atom to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Co(2)O4 tetrahedra,  an edgeedge with one Mg(1)O4 tetrahedra,  an edgeedge with one Co(1)O4 tetrahedra,  an edgeedge with one Co(2)O4 tetrahedra, and edges with two equivalent Na(7)O5 trigonal bipyramids. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to one O(1), one O(6), and one O(8) atom. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(5) atom. In the fourth Na site, Na(4) is bonded in a 4-coordinate geometry to one O(4), one O(5), one O(6), and one O(7) atom. In the fifth Na site, Na(5) is bonded in a 4-coordinate geometry to one O(2), one O(4), one O(5), and one O(7) atom. In the sixth Na site, Na(6) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(3), one O(6), and one O(8) atom. In the seventh Na site, Na(7) is bonded to one O(1), one O(2), one O(3), one O(6), and one O(8) atom to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(1)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra,  an edgeedge with one Mg(1)O4 tetrahedra,  an edgeedge with one Co(1)O4 tetrahedra, and edges with two equivalent Na(1)O5 trigonal bipyramids. In the eighth Na site, Na(8) is bonded in a distorted see-saw-like geometry to one O(4), one O(6), one O(7), and one O(8) atom. Mg(1) is bonded to one O(2), one O(3), one O(5), and one O(7) atom to form MgO4 tetrahedra that share  a cornercorner with one Co(1)O4 tetrahedra, corners with three equivalent Co(2)O4 tetrahedra,  a cornercorner with one Na(1)O5 trigonal bipyramid,  an edgeedge with one Na(1)O5 trigonal bipyramid, and  an edgeedge with one Na(7)O5 trigonal bipyramid. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(6), one O(7), and one O(8) atom to form CoO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Na(7)O5 trigonal bipyramid,  an edgeedge with one Na(1)O5 trigonal bipyramid, and  an edgeedge with one Na(7)O5 trigonal bipyramid. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form distorted CoO4 tetrahedra that share corners with three equivalent Mg(1)O4 tetrahedra,  a cornercorner with one Na(1)O5 trigonal bipyramid, corners with two equivalent Na(7)O5 trigonal bipyramids, and  an edgeedge with one Na(1)O5 trigonal bipyramid. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Na(2), one Na(3), one Na(6), one Na(7), and one Co(1) atom to form distorted ONa5Co octahedra that share  an edgeedge with one O(5)Na4MgCo octahedra, edges with two equivalent O(3)Na4MgCo octahedra, and edges with two equivalent O(6)Na5Co octahedra. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Na(1), one Na(3), one Na(5), one Na(7), one Mg(1), and one Co(2) atom. In the third O site, O(3) is bonded to one Na(1), one Na(3), one Na(6), one Na(7), one Mg(1), and one Co(2) atom to form distorted ONa4MgCo octahedra that share  an edgeedge with one O(6)Na5Co octahedra, edges with two equivalent O(5)Na4MgCo octahedra, and edges with two equivalent O(1)Na5Co octahedra. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Na(4), one Na(5), one Na(8), and one Co(2) atom. In the fifth O site, O(5) is bonded to one Na(1), one Na(3), one Na(4), one Na(5), one Mg(1), and one Co(2) atom to form distorted ONa4MgCo octahedra that share  a cornercorner with one O(6)Na5Co octahedra,  an edgeedge with one O(1)Na5Co octahedra, and edges with two equivalent O(3)Na4MgCo octahedra. The corner-sharing octahedral tilt angles are 18°. In the sixth O site, O(6) is bonded to one Na(2), one Na(4), one Na(6), one Na(7), one Na(8), and one Co(1) atom to form distorted ONa5Co octahedra that share  a cornercorner with one O(5)Na4MgCo octahedra,  an edgeedge with one O(3)Na4MgCo octahedra, and edges with two equivalent O(1)Na5Co octahedra. The corner-sharing octahedral tilt angles are 18°. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Na(4), one Na(5), one Na(8), one Mg(1), and one Co(1) atom. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Na(6), one Na(7), one Na(8), and one Co(1) atom. is represented by the CIF file [CIF]
data_Na8Mg(CoO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.786
_cell_length_b   5.870
_cell_length_c   8.856
_cell_angle_alpha   72.192
_cell_angle_beta   80.057
_cell_angle_gamma   68.940
_symmetry_Int_Tables_number   1
_cell_volume   266.609
_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
  Na  Na0  1  0.945  0.745  0.310  1.0
  Na  Na1  1  0.472  0.370  0.936  1.0
  Na  Na2  1  0.460  0.237  0.326  1.0
  Na  Na3  1  0.433  0.084  0.728  1.0
  Na  Na4  1  0.915  0.445  0.635  1.0
  Na  Na5  1  0.428  0.856  0.143  1.0
  Na  Na6  1  0.977  0.317  0.179  1.0
  Na  Na7  1  0.035  0.627  0.844  1.0
  Mg  Mg8  1  0.888  0.057  0.530  1.0
  Co  Co9  1  0.978  0.002  0.974  1.0
  Co  Co10  1  0.454  0.695  0.494  1.0
  O  O11  1  0.715  0.079  0.121  1.0
  O  O12  1  0.720  0.434  0.407  1.0
  O  O13  1  0.195  0.975  0.379  1.0
  O  O14  1  0.275  0.517  0.631  1.0
  O  O15  1  0.660  0.861  0.539  1.0
  O  O16  1  0.182  0.188  0.947  1.0
  O  O17  1  0.872  0.057  0.761  1.0
  O  O18  1  0.174  0.653  0.071  1.0
[/CIF]
.
The crystal structure described by Na8Mg(CoO4)2 crystallizes in the triclinic P1 space group. There are eight inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(8) atom to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Co(2)O4 tetrahedra,  an edgeedge with one Mg(1)O4 tetrahedra,  an edgeedge with one Co(1)O4 tetrahedra,  an edgeedge with one Co(2)O4 tetrahedra, and edges with two equivalent Na(7)O5 trigonal bipyramids. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to one O(1), one O(6), and one O(8) atom. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(5) atom. In the fourth Na site, Na(4) is bonded in a 4-coordinate geometry to one O(4), one O(5), one O(6), and one O(7) atom. In the fifth Na site, Na(5) is bonded in a 4-coordinate geometry to one O(2), one O(4), one O(5), and one O(7) atom. In the sixth Na site, Na(6) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(3), one O(6), and one O(8) atom. In the seventh Na site, Na(7) is bonded to one O(1), one O(2), one O(3), one O(6), and one O(8) atom to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one Co(1)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra,  an edgeedge with one Mg(1)O4 tetrahedra,  an edgeedge with one Co(1)O4 tetrahedra, and edges with two equivalent Na(1)O5 trigonal bipyramids. In the eighth Na site, Na(8) is bonded in a distorted see-saw-like geometry to one O(4), one O(6), one O(7), and one O(8) atom. Mg(1) is bonded to one O(2), one O(3), one O(5), and one O(7) atom to form MgO4 tetrahedra that share  a cornercorner with one Co(1)O4 tetrahedra, corners with three equivalent Co(2)O4 tetrahedra,  a cornercorner with one Na(1)O5 trigonal bipyramid,  an edgeedge with one Na(1)O5 trigonal bipyramid, and  an edgeedge with one Na(7)O5 trigonal bipyramid. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(6), one O(7), and one O(8) atom to form CoO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Na(7)O5 trigonal bipyramid,  an edgeedge with one Na(1)O5 trigonal bipyramid, and  an edgeedge with one Na(7)O5 trigonal bipyramid. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form distorted CoO4 tetrahedra that share corners with three equivalent Mg(1)O4 tetrahedra,  a cornercorner with one Na(1)O5 trigonal bipyramid, corners with two equivalent Na(7)O5 trigonal bipyramids, and  an edgeedge with one Na(1)O5 trigonal bipyramid. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Na(2), one Na(3), one Na(6), one Na(7), and one Co(1) atom to form distorted ONa5Co octahedra that share  an edgeedge with one O(5)Na4MgCo octahedra, edges with two equivalent O(3)Na4MgCo octahedra, and edges with two equivalent O(6)Na5Co octahedra. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Na(1), one Na(3), one Na(5), one Na(7), one Mg(1), and one Co(2) atom. In the third O site, O(3) is bonded to one Na(1), one Na(3), one Na(6), one Na(7), one Mg(1), and one Co(2) atom to form distorted ONa4MgCo octahedra that share  an edgeedge with one O(6)Na5Co octahedra, edges with two equivalent O(5)Na4MgCo octahedra, and edges with two equivalent O(1)Na5Co octahedra. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Na(4), one Na(5), one Na(8), and one Co(2) atom. In the fifth O site, O(5) is bonded to one Na(1), one Na(3), one Na(4), one Na(5), one Mg(1), and one Co(2) atom to form distorted ONa4MgCo octahedra that share  a cornercorner with one O(6)Na5Co octahedra,  an edgeedge with one O(1)Na5Co octahedra, and edges with two equivalent O(3)Na4MgCo octahedra. The corner-sharing octahedral tilt angles are 18°. In the sixth O site, O(6) is bonded to one Na(2), one Na(4), one Na(6), one Na(7), one Na(8), and one Co(1) atom to form distorted ONa5Co octahedra that share  a cornercorner with one O(5)Na4MgCo octahedra,  an edgeedge with one O(3)Na4MgCo octahedra, and edges with two equivalent O(1)Na5Co octahedra. The corner-sharing octahedral tilt angles are 18°. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Na(4), one Na(5), one Na(8), one Mg(1), and one Co(1) atom. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Na(6), one Na(7), one Na(8), and one Co(1) atom. is represented by the CIF file [CIF]
data_Na8Mg(CoO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.786
_cell_length_b   5.870
_cell_length_c   8.856
_cell_angle_alpha   72.192
_cell_angle_beta   80.057
_cell_angle_gamma   68.940
_symmetry_Int_Tables_number   1
_cell_volume   266.609
_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
  Na  Na0  1  0.945  0.745  0.310  1.0
  Na  Na1  1  0.472  0.370  0.936  1.0
  Na  Na2  1  0.460  0.237  0.326  1.0
  Na  Na3  1  0.433  0.084  0.728  1.0
  Na  Na4  1  0.915  0.445  0.635  1.0
  Na  Na5  1  0.428  0.856  0.143  1.0
  Na  Na6  1  0.977  0.317  0.179  1.0
  Na  Na7  1  0.035  0.627  0.844  1.0
  Mg  Mg8  1  0.888  0.057  0.530  1.0
  Co  Co9  1  0.978  0.002  0.974  1.0
  Co  Co10  1  0.454  0.695  0.494  1.0
  O  O11  1  0.715  0.079  0.121  1.0
  O  O12  1  0.720  0.434  0.407  1.0
  O  O13  1  0.195  0.975  0.379  1.0
  O  O14  1  0.275  0.517  0.631  1.0
  O  O15  1  0.660  0.861  0.539  1.0
  O  O16  1  0.182  0.188  0.947  1.0
  O  O17  1  0.872  0.057  0.761  1.0
  O  O18  1  0.174  0.653  0.071  1.0
[/CIF]
.