The material described by Na4Mg(FeO3)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 4-coordinate geometry to one O(1), one O(3), 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(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted MgO5 trigonal bipyramids that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Fe(2)O4 tetrahedra,  an edgeedge with one Fe(1)O4 tetrahedra, and  an edgeedge with one Fe(2)O4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form FeO4 tetrahedra that share corners with two equivalent Fe(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 Fe site, Fe(2) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form FeO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, 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 5-coordinate geometry to one Na(1), two equivalent Na(2), one Mg(1), and one Fe(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 Fe(2) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to two equivalent Na(1), one Mg(1), one Fe(1), and one Fe(2) atom. In the fourth O site, O(4) is bonded in a tetrahedral geometry to two equivalent Na(2), one Fe(1), and one Fe(2) atom. is represented by the CIF card [CIF]
data_Na4Mg(FeO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.241
_cell_length_b   6.497
_cell_length_c   5.144
_cell_angle_alpha   90.219
_cell_angle_beta   90.457
_cell_angle_gamma   61.296
_symmetry_Int_Tables_number   1
_cell_volume   182.922
_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  0.894  0.601  0.492  1.0
  Na  Na1  1  0.492  0.660  0.013  1.0
  Na  Na2  1  0.495  0.399  0.492  1.0
  Na  Na3  1  0.152  0.340  0.013  1.0
  Mg  Mg4  1  0.557  0.000  0.669  1.0
  Fe  Fe5  1  0.837  0.000  0.063  1.0
  Fe  Fe6  1  0.140  1.000  0.562  1.0
  O  O7  1  0.809  0.742  0.931  1.0
  O  O8  1  0.463  0.754  0.508  1.0
  O  O9  1  0.551  0.258  0.931  1.0
  O  O10  1  0.217  0.246  0.508  1.0
  O  O11  1  0.840  0.000  0.443  1.0
  O  O12  1  0.126  0.000  0.940  1.0
[/CIF]
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The material described by Na4Mg(FeO3)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 4-coordinate geometry to one O(1), one O(3), 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(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted MgO5 trigonal bipyramids that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Fe(2)O4 tetrahedra,  an edgeedge with one Fe(1)O4 tetrahedra, and  an edgeedge with one Fe(2)O4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form FeO4 tetrahedra that share corners with two equivalent Fe(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 Fe site, Fe(2) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form FeO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, 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 5-coordinate geometry to one Na(1), two equivalent Na(2), one Mg(1), and one Fe(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 Fe(2) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to two equivalent Na(1), one Mg(1), one Fe(1), and one Fe(2) atom. In the fourth O site, O(4) is bonded in a tetrahedral geometry to two equivalent Na(2), one Fe(1), and one Fe(2) atom. is represented by the CIF card [CIF]
data_Na4Mg(FeO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.241
_cell_length_b   6.497
_cell_length_c   5.144
_cell_angle_alpha   90.219
_cell_angle_beta   90.457
_cell_angle_gamma   61.296
_symmetry_Int_Tables_number   1
_cell_volume   182.922
_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  0.894  0.601  0.492  1.0
  Na  Na1  1  0.492  0.660  0.013  1.0
  Na  Na2  1  0.495  0.399  0.492  1.0
  Na  Na3  1  0.152  0.340  0.013  1.0
  Mg  Mg4  1  0.557  0.000  0.669  1.0
  Fe  Fe5  1  0.837  0.000  0.063  1.0
  Fe  Fe6  1  0.140  1.000  0.562  1.0
  O  O7  1  0.809  0.742  0.931  1.0
  O  O8  1  0.463  0.754  0.508  1.0
  O  O9  1  0.551  0.258  0.931  1.0
  O  O10  1  0.217  0.246  0.508  1.0
  O  O11  1  0.840  0.000  0.443  1.0
  O  O12  1  0.126  0.000  0.940  1.0
[/CIF]
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