The material structure described by Na4Mg(CoO3)2 crystallizes in the monoclinic Cm 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(3), two equivalent O(1), and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to one O(4), two equivalent O(1), and two equivalent O(2) atoms. Mg(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted MgO5 trigonal bipyramids that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(1)O4 trigonal pyramid,  an edgeedge with one Co(2)O4 tetrahedra, and  an edgeedge with one Co(1)O4 trigonal pyramid. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form distorted CoO4 trigonal pyramids that share corners with two equivalent Co(2)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. In the second Co site, Co(2) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form CoO4 tetrahedra that share  a cornercorner with one Mg(1)O5 trigonal bipyramid, corners with two equivalent Co(1)O4 trigonal pyramids, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Na(1), two equivalent Na(2), one Mg(1), and one Co(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Na(1), two equivalent Na(2), one Mg(1), and one Co(2) atom. In the third O site, O(3) is bonded to two equivalent Na(1), one Co(1), and one Co(2) atom to form corner-sharing ONa2Co2 tetrahedra. In the fourth O site, O(4) is bonded to two equivalent Na(2), one Mg(1), one Co(1), and one Co(2) atom to form distorted corner-sharing ONa2MgCo2 trigonal bipyramids. is represented by the CIF card [CIF]
data_Na4Mg(CoO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.102
_cell_length_b   6.504
_cell_length_c   5.039
_cell_angle_alpha   89.109
_cell_angle_beta   88.100
_cell_angle_gamma   62.023
_symmetry_Int_Tables_number   1
_cell_volume   176.524
_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  0.854  0.662  0.508  1.0
  Na  Na1  1  0.492  0.610  0.983  1.0
  Na  Na2  1  0.516  0.338  0.508  1.0
  Na  Na3  1  0.102  0.390  0.983  1.0
  Mg  Mg4  1  0.442  0.000  0.181  1.0
  Co  Co5  1  0.856  1.000  0.044  1.0
  Co  Co6  1  0.156  0.000  0.566  1.0
  O  O7  1  0.792  0.752  0.006  1.0
  O  O8  1  0.445  0.740  0.444  1.0
  O  O9  1  0.544  0.248  0.006  1.0
  O  O10  1  0.185  0.260  0.444  1.0
  O  O11  1  0.875  1.000  0.432  1.0
  O  O12  1  0.169  0.000  0.947  1.0
[/CIF]
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The material structure described by Na4Mg(CoO3)2 crystallizes in the monoclinic Cm 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(3), two equivalent O(1), and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to one O(4), two equivalent O(1), and two equivalent O(2) atoms. Mg(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted MgO5 trigonal bipyramids that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(1)O4 trigonal pyramid,  an edgeedge with one Co(2)O4 tetrahedra, and  an edgeedge with one Co(1)O4 trigonal pyramid. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form distorted CoO4 trigonal pyramids that share corners with two equivalent Co(2)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. In the second Co site, Co(2) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form CoO4 tetrahedra that share  a cornercorner with one Mg(1)O5 trigonal bipyramid, corners with two equivalent Co(1)O4 trigonal pyramids, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Na(1), two equivalent Na(2), one Mg(1), and one Co(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Na(1), two equivalent Na(2), one Mg(1), and one Co(2) atom. In the third O site, O(3) is bonded to two equivalent Na(1), one Co(1), and one Co(2) atom to form corner-sharing ONa2Co2 tetrahedra. In the fourth O site, O(4) is bonded to two equivalent Na(2), one Mg(1), one Co(1), and one Co(2) atom to form distorted corner-sharing ONa2MgCo2 trigonal bipyramids. is represented by the CIF card [CIF]
data_Na4Mg(CoO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.102
_cell_length_b   6.504
_cell_length_c   5.039
_cell_angle_alpha   89.109
_cell_angle_beta   88.100
_cell_angle_gamma   62.023
_symmetry_Int_Tables_number   1
_cell_volume   176.524
_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  0.854  0.662  0.508  1.0
  Na  Na1  1  0.492  0.610  0.983  1.0
  Na  Na2  1  0.516  0.338  0.508  1.0
  Na  Na3  1  0.102  0.390  0.983  1.0
  Mg  Mg4  1  0.442  0.000  0.181  1.0
  Co  Co5  1  0.856  1.000  0.044  1.0
  Co  Co6  1  0.156  0.000  0.566  1.0
  O  O7  1  0.792  0.752  0.006  1.0
  O  O8  1  0.445  0.740  0.444  1.0
  O  O9  1  0.544  0.248  0.006  1.0
  O  O10  1  0.185  0.260  0.444  1.0
  O  O11  1  0.875  1.000  0.432  1.0
  O  O12  1  0.169  0.000  0.947  1.0
[/CIF]
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